Electronics

regulator IC

2012-02-13T06:46:00.000-08:00

Rectifier circuit is good enough if the voltage ripple is small, but there are stability issues. If PLN voltage up / down, then the output voltage will also rise / fall. As rectifier circuit above, if the greater flow of dc discharge voltage was also decreased. For some applications this voltage change is quite annoying, so it requires the active components that can regulate the output voltage becomes stable.

Voltage regulators voltage serves as a filter to suit. Therefore, it is usually in a series of power supply the voltage regulator IC is always used for stabilizing the voltage out put.

The following arrangement of the regulator IC legs.

For example, 7805 is a voltage regulator to get a +5 volt, +12 volt voltage regulator 7812 and beyond. While the 79XX series is the 7905 and 7912 such that a row is a voltage regulator -5 and -12 volts.

Apart from a fixed voltage regulators have a voltage regulator IC is also adjustable. The principle is the same as the OP-amp regulator packaged in a single IC for regulators such as LM317 and LM337 variable positive to negative variable regulator. The difference between resistor R1 and R2 are outside the IC, so the output voltage can be set via external resistors.

The simplest regulator circuit shown in figure 6. In this circuit, zener breakdown work in the area, thereby producing an output voltage equal to or zener voltage Vout = Vi. But this series is only useful if the load current not exceeding 50mA.

The principle of the power supply circuit is called a shunt regulator, one of his trademark is the component parallel to the load regulator. Another characteristic of the shunt regulator is susceptible to short-circuit. Note if Vout connected short (short-circuit) then the current is fixed I = Vin/R1. Besides the shunt regulator, there is also called a series regulator. The main principle of such series regulator circuit in Figure 7 below. In this circuit the output voltage is:

Vout = VZ + VBE

VBE is the base-emitter voltage of transistor Q1 which is between 0.2 - 0.7 volts depending on the type of transistor used. By ignoring the IB currents flowing in the transistor base, R2 can be calculated of the prisoners are required are:

R2 = (Vin - Vi) / Iz

Iz is the minimum flow required by the zener diode breakdown voltage zener to achieve it. Large currents can be known from the datasheet that the amount of approximately 20 mA.

If needed supply a larger current, base current IB of the calculations in the above circuit can not be ignored anymore. Where as is known, a large flow of IC will be directly proportional to the flow defined by IB or IC = Bib. For this purpose, the transistor Q1 is used can be replaced with a Darlington transistor usually has a value of b is large enough. With a Darlington transistor, the current small base current can produce a larger IC.

Techniques that better regulation is to use the Op-Amp to drive a transistor Q, as shown in figure 8 circuit. Zener diodes are not here to give direct feedback to the transistor Q, but as a reference voltage for IC1 Op-Amp. Pin negative feedback on the Op-amp is an excerpt from the voltage regulator out, namely:

Vin (-) = (R2 / (R1 + R2)) Vout

If the voltage Vout ascending out, the voltage Vin (-) will also be upward until the voltage is equal to the reference voltage Vi. And vice versa if the voltage Vout decreases exit, such as the supply current to the load increases, the op-amp will maintain stability in a given reference point Vi IB flows to the transistor Q1. So at all times maintain the stability of Op-amp:

Vin (-) = ½

By ignoring the voltage VBE of transistors Q1 and mensubsitusi formula (11) into the formula (10) is obtained by the mathematical relationship:

Vout = ((R1 + R2) / R2) ½

In this circuit the output voltage can be set to adjust the R1 and R2.

Now it should no longer have to laboriously search for op-amps, transistors and other components to realize the regulator circuit as above. Because these circuits are packed into a fixed voltage regulator IC. Are now widely known as the 78XX series parts stayed positive voltage regulator and the 79XX series is a negative regulator for a fixed voltage. In fact, these components are usually already equipped with current limiting (current limiter) and also the limiting temperature (thermal shutdown). This component is only three pins, and by adding some components alone can be a power supply circuit that was a good regulation.

It's just note that the IC regulator circuit can work, the input voltage must be greater than the output voltage regulators. Usually the difference in voltage Vin to Vout recommended in the datasheet component. Use of heat sink (aluminum coolers) is recommended if these components are used for supply large currents. In the datasheet, this component can pass through the flow reaches a maximum of 1 A.

Parts of the tuner

2012-02-13T05:43:00.000-08:00

Parts of the tuner:
A. The selection of channels (selection transmitting stations)
Tuner blocks to choose the wave transmitter to be received, including channel 2 to channel 12 (47-230 MHz) in VHF and each channel has a width of the frequency of 7 MHz. Circuit tuning can be chosen so that resonance the frequency channel of your choice.
In the tuner block are RF amplifier, Mixer and Oscillator. RF amplifier to choose the transmitter to be received, and then supplied to the mixer, oscillator generating a frequency of certain magnitude to the comparison frequency to be received RF amplifier is then supplied to the mixer and the filter eventually produce a new frequency is out of the 38.9 MHz is the carrier frequency images therein there is a synchronization signal and 33.4 MHz is the frequency of sound carrier and the second frequency is forwarded to the video amplifier IF.

2. Amplifier of high frequency (HF Amplifier)
Prior to the series mixing (mixing) wave tv amplified by the amplifier HF. Because the ratio S / N (the comparison signal / noise) at the receiver a color TV set by amplifier HF, then strengthening HF should be able to produce amplifier (gain) is great. Also requires a distortion of small even when a wave of TV a large input. Then the required voltage AGC (Automatic Gain Control / control amplifier automatically) to the amplifier HF was mounted a series of neutralization, the amplifier HF to prevent parasitic oscillation occurs. Characteristic frequency response of the amplifier HF in the field of frequency channel receiver, must be equal as possible and the difference reinforcement between the canals received should be as small as possible.

3. Mixer (Mixer)
Wave TV received TV mixed with the output local oscillator using a mixer (mixer) and converted into a signal IF (Intermediate) images that have a frequency equal to the difference in both frequency earlier. The carrier frequency signal IF the image is 38.9 MHz and the carrier frequency of the sound signal is 33.4 MHz.

Canal No. 3:
Frequency Osc
38.9 MHz
33.4 MHz

55.25 60.75 95.15 MHz

4. Local oscillator
Frequency mixer (Frequency local) generated by local oscillator, and supplied to the mixer (Mixer). Frequency can be changed depending on the channel selected recipients.
As the local oscillator is usually used oscillator Colpitts because of the nature of its stability and simple structure his series. There are two ways to choose the frequency of the first local by changing the coil resonance and the second by controlling the bias voltage of the diode capacitance is variable.

Operational Amplifier

2012-02-13T04:54:00.000-08:00

Operational Amplifier (Op-Amp) is a differential amplifier into a high trailer directly.

Op Amp is a circuit that generates the output voltage V0, which is the result of the strengthening of the difference in the two input voltages V1 and V2.

Op-Amp Characteristics
Acquisition of infinite voltage.
Bandwidth is not infinite.
Enter an infinite impedance.
Out zero impedance.
Complete balance sheet, which is zero if the output voltages at the same time there are two input terminals.
Characteristics are not changed by temperature.

DC power

2012-02-13T04:43:00.000-08:00

The PS10 power supply provide +15 Volt and -15 Volt regulated DC power at up to 250 mA of current per output. The two outputs have a common ground connection. The outputs are short circuit proof. A thermal protection turns the outputs off when the circuit is overheated. A low input to output stray capacitance guaranties a low AC leakage current and makes the PS10 well suited in applications where low hum and noise is important, such as low level pre-amplifiers and audio applications. The PS10 uses a dual winding AC transformer. A Light Emitting Diode at each output indicates proper output voltage.

Specifications
Output voltage: . . . . . . . . . . . . . +/- 15 Volt, +/- 5%
Max continuous output current:. . . . . . 250 mA each channel
Output short circuit current: . . . . . . 1.5A, typical.
Nominal input voltage:. . . . . . . . . . 115/230VAC, 50/60 Hz
Output voltage ripple:. . . . . . . . . . less than 10mV, @ 60 Hz, 250 mA load
Output voltage regulation:. . . . . . . . better then 10 mV
Input to Output capacitance:. . . . . . . 50 pF Max.
Dimensions (L X W X H): . . . . . . . . . 4.3" X 2.0" X 1.5"
Ordering Information

PS10-B Bare board with manual
PS10-K Kit with manual and all parts
PS10-A Fully assembled and tested
PS10-M Manual only

Power supply 5 volts 5 A with a pass transistor

2012-02-13T03:57:00.000-08:00

Power supply 5 volts 5 A with a pass transistor

By using 7805 components, it can easily be made a series of excellent power supply output voltage regulation. However, the component 7805 can only be effectively distribute the current to 1 A only. 5 volt power supply is generally used to distribute many different applications, so it sometimes is not enough supply current 1A.

In this article presents the design electroniclab regulated 5 volt power supply that can supply enough current to 5 A, at least it is ever tested in the workshop electroniclab. Actually, this circuit could distribute up to 10 A or even more if the reader know tips to modify it.

The core of this circuit certainly is a basic circuit with a 7805 5 volt regulator. The difference is, the series pass transistor is added to the circuit consisting of transistors Q1 and 2 pieces of resistors R1 and R2. 7805 components in control regulates the output voltage, and a series pass transistor is essential to drain the remaining current to the load RL.

The transistors used are the MJ2955 PNP transistor. Transistor is known as silicon bipolar power transistors are often found in the market. Readers can in principle be replace it with other bipolar power transistor, provided with similar characteristics. From the datasheet, it is known that the category of transistor power transistor collector current Ic as 15A can be achieved with power dissipation that can reach 115 watts. Of course in designing a series of maximum limits should be aware of this, so it does not exceed the optimum can be achieved.

Note the series of images above. In the closed-loop current through the resistor R1, R2 and the emitter-base transistor Q1, can be formulated mathematically:

I1R1 = IeR2 + VBE (on) â € | â € | â € | (1)

For silicon transistors usually VBE (on) = 0.7 volts, the base-emitter voltage causes transistor starts working (ON). This voltage is known from the datasheet VBE (on) this can vary between 0.6 ~ 1.4 volts depending on which of the current Ic through the transistor. But for the simplification of the calculation, we set the course VBE (on) = 0.7 volts.

I1 is the current through the 7805 onwards will supply the load RL. With this series we will be setting a large current through 7805, for example if you set current I1 = 500 mA. So how to supply current to the load RL to 5A? Of course the rest would flow MJ2955 is passed through the transistor. Of formula (1) it is understandable that the current passing through R2 Ie will begin to flow only when the voltage across the resistor R1 flops greater than VBE (on) or mathematically:

I1R1> = VBE (on) â € |. (2)

If the magnitude of the above disubsitusikan to formula (2) of the R1 can be calculated that is required is:

R1 = VBE (0n) / I1 = 0.7/0.5 = 1.4 Ohm

How to set a large current I1 = 500 mA, may be whether more or less. If we trace back a little, we first want to make a power supply with Io = 5 A. In the above circuit, Io = Ic + IOA € ™. If we consider the IOA € ™ is quite small compared to Ic, then Ic = Io can be written. Of transistor known theory that Ic = Hfe Ib. MJ2955 datasheet from Hfe big unknown is 20 ~ 70. You can search for a transistor with Hfe = 50. If this is used, then that must be supplied base current is Ib = Ic / Hfe = 5/50 = 100 mA. With this calculation is not wrong if it is assumed to be masksimum current of 500 mA through R1. Because it will supply enough base current Ib (at 100 mA) required to supply current Ic transistor Q1 to 5 A.

Great resistance R2 can be calculated from Vin to Vout loop through the transistor Q1 is defined by:

Vin = IeR2 + VCE (on) + Vout â € |. (3)

Vin is the voltage output of the rectifier circuit made of a series transformer, diode bridge and capacitor elco. If for example Vin = 7 volts and the output voltage Vout = 5 volts, then the formula (3) can ditullis be:

+ 7 = IeR2 VCE (on) + 5

or

IeR2 + VCE (on) = 2 volts â € | .. (4)

This is the line or lines of work load transistor Q1. Assuming that Ie = Ic = 5 A and VCE (on) = 0 volts (ideal) when the transistor Q1 is working (ON), then it can be calculated of R2 = 2/5 = 0.4 Ohm. Finish â € |? of course not, because it must be specified wattage of the resistor is large. Of the general formula P = I2R power dissipation can be calculated on the resistor R2 is P = 52 (0.4) = 10 watts (minimum), then used the 0.4 Ohm 20 watt resistor to be safe.

Thus the sequence of this power supply design. Of course this design can be modified as needed. For tips last, With such a large current, temperature resistors and transistors will be so hot. Highly recommended to use a heatsink for the transistor Q1 and also R2 resitor. 7805 component should not require a heatsink, because the current through this component is relatively small. Elco capacitor C1 is the recommendation of the 7805 datasheet for more stable output voltage.

To the needs of larger currents, transistor Q1 can be replaced with a Darlington transistor, or a way to pass transistor cascade circuit into 2 or 3 level. In principle, the above calculations can also be applied to other power supply circuit design such as 12 volts or 24 volts.

DIAC structure

2012-02-12T05:17:00.000-08:00

When viewed the structure as shown below, not including DIAC thyristor family, but his principle of making it is classified as a thyristor. DIAC is made with structures similar to the PNP transistor. N layer on a transistor made so thin that electrons can easily penetrate across this layer. While at DIAC, N layer is made thick enough so that the electron is quite difficult to penetrate. DIAC structure which can thus also be viewed as two PN diode and the NP, resulting in some literature DIAC classified as a diode.

Difficult to be passed by two-way flow, DIAC was intended for this purpose. Only with a specific breakdown voltage before DIAC can conduct current. Current course can be delivered back and forth from the anode to the cathode and vice versa. DIAC same characteristic curve as TRIAC, but that just need to know is how its breakdown voltage.
Symbol of the DIAC is as shown in the image above. DIAC is generally used as a trigger ON the TRIAC to a specific input voltage is relatively high. An example is the following lamp dimmer applications in the figure below:

If it is known in the circuit TRIAC IGT of 10 mA and above the VGT = 0.7 volts. And note also that is used is a DIAC with VBO = 20 V, the TRIAC will be calculated on the ON voltage:
V = IGT (R) + VBO + VGT = 120.7 V

On a dimmer circuit, the resistor R is usually replaced with series resistors and potentiometers. Here with a series capacitor C R is used to shift the phase voltage VAC.

Null Modem

2012-02-12T05:00:00.000-08:00

Null Modem configurations are used to connect two DTE with a wiring diagram that can be seen in the image below. In this case it only takes three wires between the DTE, which is to TxD, RxD and Gnd. The way it works is how to make the computer into thinking that the computer communicates with the modem (DCE) rather than with other computers.

In the picture above shows that the foot DTR (Data Terminal Ready) is connected to the DSR (Data Set Ready) and also to the CD (Carrier Detect) on each computer, so that when the DTR signal is activated then DSR and CD signals also active (Modem concepts Virtual Modem or pseudo). Because the computer in this case sending data at the same speed, the flow control (flow control) is not required so that the RTS (Request To Send) and CTS (Clear to Send) on each computer connected to each other.

Data transmission in RS232
The RS-232 communication with PC is asynchronous communication. Where clocknya signal is not sent along with the data. Each data synchronized using the internal clock on each side. Figure 2.6 Format of transmission of the RS232 Data byte transmitted in the above format is 8 bits, before the data is transmitted it will be preceded by a start bit to logic 0 (0 volts), then 8 bits of data and is terminated by a stop bit to logic 1 ( 5 Volt).

Advantages of Using Serial Communications
Serial communications interface offers several advantages compared with parallel communication, including:

• Cables for serial communication can be longer than parallel.
The data in the serial communication is sent to logic '1 'as the voltage of -3 s / d and -25 volts for logic '0' as the voltage of +3 s / d +25 volts, thus the voltage in serial communication has a maximum voltage swing of 50 volts, while the parallel communication is only 5 volts. This causes disruption in the wiring length is more easily overcome than the parallel.

• The number of serial cable less.
Two sets of a remote computer with only three cables to null modem configuration, ie, TxD (send channel), RxD (receive channel) and the Ground, but if you use parallel communication there will be twenty to twenty-five wires.

• Serial communications can use the free air as the transmission medium.
In the serial communication is transmitted one bit at a time so that when the transmission using a media-free air (free space) then the receiver section will not appear difficult to reconstruct the bits of bits transmitted.

• Serial communications can be applied to communicate with the microcontroller.
It only takes two main pin TxD and RxD (outside the reference ground).

RS232

2012-02-12T04:47:00.000-08:00

RS232 standard set by the Electronic Industry Association and Telecommunications Industry Association in 1962. His full name is EIA/TIA-232 Interface Between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange. Although his name is quite long but this standard is only concerned with data communication between computer equipment computer peripherals. There are two main things that set the standard RS232, among other things:

• The shape and signal voltage levels are used.

RS232 built in 1962, long before the popular TTL IC, therefore the voltage levels specified for RS232 nothing to do with TTL voltage levels, it can even be said that different. Here's the difference between RS232 and TTL voltage levels:

Determination of types of signals and connectors that are used, as well as the arrangement of the signal at the legs of the connector. Some parameters are defined EIA (Electronics Industry Association •), among others:

• A 'space' (logic 0) voltage between +3 s / d +25 volt
• A 'sign' (logic 1) voltage between -3 s / d -25 volt
• Local voltage between +3 s / d -3 volts is not defined
• open circuit voltage should not exceed 25 volts (with reference to ground)
• short circuit current of the circuit should not exceed 500 mA.

A driver (drivers) should be able to handle this current without damage. In addition to describing the voltage levels as discussed above, standard RS232 determine the types of signals are used to set the exchange of information between the DTE and DCE, are all there are 24 types of common signals but that is only 9 types of signals. Connectors used were determined in a standard RS232, for a complete signal used DB25 connectors, while the DB9 connector can only be used for commonly used signal 9.

PNPN structure

2012-02-12T04:03:00.000-08:00

Thyristor stems from the Greek word meaning 'door'. Perhaps so named because of the nature of this component is similar to that door can be opened and closed to pass an electric current. There are several components that include, among others thyristor PUT (programmable uni-junction transistor), UJT (uni-junction transistor), GTO (gate turn off switch), photo SCR and so on. But on this occasion, which will point out the components of the thyristor known as SCR (silicon controlled rectifier), TRIAC and DIAC. Readers can listen to more clearly how the working principles and their application.
thyristor structure
The main characteristics of a thyristor is a component made of silicon semiconductor material. Although the material is the same, but its PN junction structure is more complex than a bipolar or MOS transistor. Thyristor component is more used as a switch (switch) rather than as an amplifier as well as current or voltage transistor.

Basic structure of the thyristor is a four layer PNPN structure as shown in the figure above a. If sorted, this structure can be seen as two PNP and NPN junction structure are connected in the middle as shown above b. This is nothing but the two PNP and NPN transistors are connected to each collector and base. If visualized as transistors Q1 and Q2, then the thyristor structure can be displayed as shown below.

Seen here is connected to the collector of transistor Q1 base of transistor Q2 and the collector of transistor Q2 is connected opposite the base of transistor Q1. Such a transistor circuit indicate a strengthening of the current loop in the middle. Where b is known that Ic = Ib, the collector current is the strengthening of the current base.
If for example there is a current of Ib flowing to the base of transistor Q2, then there will be current Ic flowing in the collector of Q2. This collector current is the base current Ib to the transistor Q1, so it would appear on the strengthening of the current collector of the transistor Q1. Tdak transistor Q1 collector current is the current base of another transistor Q2. So forth so that the longer the PN connection of the thyristor is in the middle will shrink and disappear. Left is the P and N layers on the outside.
If this condition is reached, then such a structure is the structure of the swordfish another PN diode (anode-cathode) are already known. At such a time, called the thyristor is ON and the current can flow from the anode to the cathode such as a diode.

What if we give in this thyristor dc lamp load and rated supply voltage from zero to a certain voltage as shown above. What happens to light when a voltage is increased from zero. Yes yes, of course, the lights will remain off for the middle layer of the existing NP will get a reverse-biased (diode theory). At this time called the thyristor is turned OFF because no current can flow, or very small. Current can not flow through a reverse-bias voltage that causes certain connections and missing NP is saturated. This voltage is called breakdown voltage and current at the time it began to flow through diode thyristor as large. At this voltage thyristor breakover voltage VBO called.

MOS-FET

2012-02-12T03:37:00.000-08:00

The MOS-FET transistors on the heat sink may be tested while they are not yet connected to the transformer and the control unit. First we touch with one hand the source connections of the transistors and with the other the gate connections. This will discharge the gates. Now the source / drain connections must behave like a diode, which we can test with an ohm meter. For the next test we connect a car lamp between the drain connections of the transistors and the positive pole of a battery. The negative pole will be connected to the source of the transistors. The gate must be open. If we now touch with one hand the positive pole of the battery and with the other the gates, the lamp will light up. Now we touch the negative pole of the battery and simuntanously the gates and the lamp will be switched off. If this test is positive, the transistors are o.k.
Control unit: For testing the control unit, clamp "G" and clamp "C" must be connected to ground (minus pole). This prevents the load detection circuit from switch-off. The outputs "A" and "B" will show an output voltage between 3.5 and 4 volts. Theoretically the exact value should be 2.5 volts, according to a duty cycle of 25%, but the transformer is not yet connected and so the pulse width regulator will generate maximum value. If a frequency counter and an oscilloscope are available, the control signals may be checked and adjusted to 50 cycles or 20 milliseconds (period of the 50 cycle oscillation) at these outputs. During normal operation the transformer generates peak voltages up to 28 volts on clamp "D". The pulse width regulator may be tested, if variable DC voltages from 12 V to 28 V will be applied to this connection. For testing the current limiter, variable DC voltage may be applied to clamp "C" (0 ... 1 Volt). The switch-off should take place at about 0.35 volts.
The control unit may also be tested in connection with the mosfet transistors. Instead of the transformer, autolamps would be connected. The brightness of the lamps may now be adjusted by turning resistor R16 or connecting a DC voltage to clamp "D" as described above.
The autolamp also makes possible a very simple test to adjust the frequency. Therefore we put in series with the lamp the 12 volts output of a small tranformer, connected primarily to the mains supply. Both alternating voltages will now be added or subtracted, dependent on the phase shift. The lamp will flicker. The goal is, to make this flickering very slowly. Attention: The autolamp must be 24 volts or two lamps in series.

microcontroller

2012-02-11T21:15:00.001-08:00

microcontroller chips appear on the market, today’s microcontroller programming tools are becoming more and more ‘universal’ to cope with different programming conventions. It is also sadly the case that the more ‘universal’ the programmer, the more you need to pay. In practice, most people will only use a fraction of the capabilities of such a programmer, making it difficult to justify such an expense. The project here describes a minimal solution to the programming problem for one of the most popular types of controller. The PIC16F84 (1k-Flash-memory) and the PIC16C84 (1k-ROM) with 13 I/O-lines.

Using a PC together with this relatively simple interface and some software it is possible to build a low cost programmer The design for the programmer is described on the author’s website. The programmer connects to the serial port of a PC. Pin 3 of the port supplies the power and zener diode D6 along with D5 regulates the supply to the chip at 5 V. C1 and C2 smooth the regulated supply. The unregulated supply is fed to pin MCLR of the PIC to conﬁgure it in programming mode. R1 limits current into this pin and an internal regulator ensures the correct programming voltage on chip. A high on this pin switches the PIC into programming mode.

signal amplitude

2012-02-11T05:08:00.000-08:00

The output signal amplitude is dependent on the area of the pulses, so for accurate signal reconstruction, both time alignment and rail voltage are critical parameters. Complex audio signals will also cause intermodulation via the power supplies unless a very low impedance supply is used.

The PWM signal is generated digitally and therefore the pulse widths are quantized. Practical considerations in the power output stage limit the maximum switching frequency (fsw), although higher frequencies allow easier filtering of switching noise in the reconstruction filter. The resolution in the PWM waveform is dependent on the ratio of the Master Clock (MCK) frequency to the switching frequency, which is usually a power of 2.

The digital PCM input is also quantized: a resolution of 32 bits gives a theoretical 194dB dynamic range, if limited solely by quantization noise. More practically, 24 bits (the best resolution of today's audio ADCs) has a theoretical 144 dB dynamic range.

The PWM resolution is typically much more coarse, in order to keep switching frequency above maximum audio sample rates of 192 kHz, whilst limiting MCK frequency. Typical ratios are between 32 (5 bits) and 256 (8 bits), giving a best dynamic range of 50 dB. Clearly, this means that other techniques are required to provide sufficient dynamic range, and the answer is oversampling with noise shaping. This technique essentially allows a time averaging of the PWM pulse widths to be applied, to deliver fractional resolution in the amplitude of the output signal.

The MCK of a digital amplifier, which needs a low jitter specification for good amplifier performance, will either need to be a fixed multiple of the incoming sample rate or else can be a fixed crystal generated frequency. The first case requires a phase locked loop, which is often a source of jitter. In the second case, a sample rate converter is required to re-align the incoming oversampled data with the MCK period.

Both oversampling and sample rate conversion use interpolation and averaging filters, requiring a large number of multiply accumulates, and hence MCK cycles, which add up to a signal group delay that is significant at audio frequencies. The delay is fixed and so affects the phase of all input signal frequencies linearly, which is benign in audio terms, but must be borne in mind for any feedback system comparing output with input.

data processor

2012-02-11T04:43:00.000-08:00

A programmable logic controller (PLC) is a special data processor used as controller for machines in industrial processes. As a part of process control, a programmable logic controller is used to monitor input signals from a variety of input points which report events and conditions occurring in a controlled process. During the execution of a stored control program, they read inputs from the controlled process and, per the logic of the control program, provide outputs to the controlled process. A PLC typically consists of an input section, a logic (or processing) section, an output section, and a power supply. A PLC is typically programmed with a sequential program for controlling a machine, such as a pressing or marking machine that continuously repeats the same motions during, for example, an automated assembly process or other manufacturing process. Programmable logic controllers can be programmed using different development platforms. One common development platform is called ladder logic. Ladder logic is a programming language based on executing commands on a line-by-line permission system. Each ladder logic program comprises one or more ladder logic statements. These ladder logic statements are often termed "rungs." Each ladder logic statement defines the relationship between an output variable and one or more input variables. Programmable logic controllers are used throughout industry to control and monitor a wide range of machines and other movable components and systems. A PLC can monitor such input conditions as motor speed, temperature, pressure, volumetric flow and the like.

SPN1001-FV1

2012-02-11T04:30:00.000-08:00

The SPN1001-FV1 is a complete reverb solution in a single IC.
With integrated stereo ADC and DACs, the FV-1 can be treated like any other analog component in your products signal path.
The FV-1 can access a total of 16 programs, 8 are built in to the internal ROM and the designer may elect to connect a serial EEPROM with 8 additional programs. By using an external EEPROM, the designer can create a custom program set without the need for a microprocessor in the system.
With 3 potentiometer inputs, programs may have real time variable parameters such as decay time in a reverb, rate and depth in a chorus or frequency in a filter. These inputs are available as coefficients to your program and may be used independently of each other.
The rich instruction set allows users to program effects of all kinds. With instructions like LOG and EXP, users can easily program audio expansion and compression routines. Integrated digital LFOs and ramp generators allow for programming chorus, flange and pitch shift.

TV repair

2012-02-10T05:43:00.000-08:00

WATCHING ANY SYMPTOMS
Let TV repair done carefully and thoroughly as it can be fatal. Television is an electronic plane that has a high electrical voltage. In addition, of all the damage is not necessarily caused by the faulty component. Sometimes damaged due to poor solder tin so that the legs of components are not perfectly connected to the PCB. Symptoms and causes damage to various TV. The symptoms can be totally dead, no sound or picture produced ugly. Meanwhile, the damage can be caused by a TV that has component with age or relationship between the components is less than perfect
A. NO PICTURE AND SOUND
Dead

There is some damage that could lead to a TV set can not work at all. In general, this kind of damage occurs on the power supply (Power Supply) or the horizontal deflection circuit
What is the total dead TV and indicator lights go out?
Cause: most likely damage the power supply circuit
Solution: check the grid, a series regulator input to output
Consider the following regulator circuit schematic drawings. In general, TV has a power supply output voltage of 115 V, 24 V and 5 V, depending on the brand of TV. Replace damaged components and improve the circuit path is less than perfect. The arrows indicate the components that are easily damaged.

Is audible squeal vibration transformer switching?
Cause: The output voltage is usually blocked because of a faulty component. Solution: Remove the burden of the regulator by disconnecting the output transistor base horizontal or one foot horizontal transformer and measure the output voltage. If the output shows the voltage regulator in accordance with the instructions on the PCB, check that all the distribution channels of the output voltage regulator and a whole set of horizontal.

Consider the following horizontal circuit schematic drawings. In general, the usual components are easily damaged flyback transformer, horizontal transistor and a capacitor (see arrows).

Raster is not brightly lit screen even though the position of the maximum flyback.

Cause: The CRT anode voltage is too low due to the damage to the high voltage circuit, horizontal deflection circuit or power supply circuit. CRT cathode voltage all became great because of interference with the video amplifier. Solution: Have voltage regulator output is normal? If normal, check CRT cathode voltage. If not normal, check the regulator output voltage. Is the CRT cathode voltage normal? If normal, check the CRT anode voltage. If not normal, check the high voltage circuits.

Raster A Horizontal Line

Cause:
Sources of interference depends on the oscillator used TV.

Solution: Check the vertical deflection circuit IC Check all electrode or a transistor with multitester.

Horizontal synchronization Bad
Black strips can not be lost even if the synchronization of the raster set.

Cause:
Such damage is rare for a new TV output. If the damage happens, usually caused by a component that has been ingested age.
solution:
Check the horizontal oscillator circuit. The possibility exists that Elko is dry. Elko is usually indicated by the back that looks dull or broken.

Vertical synchronization Bad
Cause:
Damage lies in the integrator or the vertical oscillator circuit. Such damage is usually common in an older TV. Solution:
Check the vertical oscillator circuit. TV vertical output regulator may long have worn, while the new TV damage caused by leaking ceramic capacitors.

The screen image narrows
Cause:
Damage like this rarely happen on TV the new output. Lower voltage so that the horizontal output circuit current in the sawtooth horizontal deflection coil (yoke) to grow weak. Solution: Check the power supply output voltage. If a lower output voltage, check the components. Check the horizontal deflection circuit transistor is mainly present in it. Check the condition of the yoke, if it is damaged or frayed should be replaced

Horizontal Deflection Transistor
Widening the Horizontal
Cause:
Such damage is caused by a defective Vr. Solution: Check the components. If the normal power supply voltage, check the CRT anode voltage If the CRT anode voltage is too low, check the circuit Change the value of VR, if no change in the VR switch. Check the power supply output voltage. If the output voltage is larger high-voltage amplifier.

The Top Or Bottom depreciation

Cause:
Due to the value of Vr is not appropriate or electrolytic capacitors are dry.
Solution: Set VR, if no change in mean VR is broken. Check Elko are still good or it is dry
Image Vertical Aft
Cause:
Sawtooth currents on the vertical deflection coil is too low. solution:
Adjust VR, if nothing changes it may Elko is dry.

Snow Noise Figure
Cause: The field intensity at low frequencies where the signal reception. Broken TV antenna system of high-frequency amplifier circuit is damaged Solution: Rotate the antenna to get good pictures. Fix path Check the antenna cable and solder the tuner AGC block.

Low Contrast Images

Cause:
The damage is located between the mixer to the amplifier circuit video.
solution:
Check that there is a resistor whose value is enlarged or short.

Black Horizontal lines
Cause:
Usually caused by a device that uses a small motor. solution:
Keep away from sources of noise of the TV.

Disturbed by Channel Picture Other
Cause:
Cross-modulation occurs by a channel that has a large emittance. Solution: Adjust the TV antenna height Set the value of Vr AGC circuit

PULSE Sources

2012-01-30T02:42:00.000-08:00

PULSE Sources

This type of source can be either a voltage or a current source. We often use it as a stimulus for transient response simulation of a circuit. It should never be used in a frequency response study because the model assumes it is in the time domain. The designation of the pulse source starts as any other independent source; i.e., the part name must begin with the letter V (for voltage) or I (for current). This is followed by the node names. Then, instead of "DC" or "AC," we use the keyword "PULSE" followed by the necessary parameter list. Items in the parameter list may be separated by spaces or commas. An example of a pulse type of voltage source follows:

The parameters for the pulse (to be entered in the order given) are:

V1 is the value when the pulse is not "on." This can be zero or negative as required. For a pulsed current source, the units would be "amps" instead of "volts."
V2 is the value when the pulse is fully turned on. This can also be zero or negative. (Obviously, V1 and V2 should not be equal.) Again, the units would be "amps" if this were a current pulse.
Td is the time delay. The default units are seconds. The time delay may be zero, but not negative.
Tr is the rise time of the pulse. PSpice allows this value to be zero, but zero rise time may cause convergence problems in some transient analysis simulations; i.e., there is a very good reason for the existence of this parameter. The default units are seconds.
Tf is the fall time in seconds of the pulse. See note on Tr before setting this to zero.
Tw is the pulse width. This is the time in seconds that the pulse is fully on.
Period is the total time in seconds of the pulse. Be aware that the pulse repeats if the simulation time exceeds the period.

Zener Voltage

2012-01-29T17:40:00.000-08:00

Zener Voltage
Zener diode is a diode that has the characteristics of the channel the electrical current flowing in the opposite direction when the applied voltage overshoot "breakdown voltage" (breakdown voltage) or "Zener voltage". This is different from ordinary diode which only transmits electrical current to one direction.

Diodes usually will not drain the electrical current to flow in the opposite if the reverse-biased (reverse-biased) below the breakdown voltage. If the operating voltage exceeds the limit, regular diode will be damaged because of excess electrical current that causes heat. However, this process is reversible if it is done within your limits. In the case of rationing-forward (in the direction of the arrow), this diode will provide voltage drop (voltage drop) of about 0.6 volts for a normal silicon diode. The voltage drop depends on the type of diode used.

semiconductor components

2012-01-22T21:59:00.000-08:00

The simplest semiconductor components, it consists of two (2) the cathode and anode electrodes.

End of the body diode is usually given a marked, a bracelet or a point, which indicates the location of the cathode.

Diodes can only DC current flowing in the direction of course, in the reverse direction DC current will not flow. If the silicon diode is energized AC currents of electricity, then that flow only in one direction only so that the flow of DC current output diode.

When given the potential positive anode and negative cathode, said diode is forward biased and when given the contrary, is said to be reverse biased diode. On the forward bias, the difference between the cathode and the anode voltage is called threshold voltage or knee voltage. Large voltage depends on the type of diode, can be 0.2V, 0.6V and so on.

When the diodes are reverse biased (which vary depending on supply voltage voltagenya) reverse voltage is called voltage. This reverse voltage must not exceed a certain price, this price is called the breakdown voltage, eg 50V sebasar 1N4001 diode type.

Eg type germanium diodes type 1N4148 or 1N60 when given forward bias can forward radio frequency vibrations, and when a forward bias is removed, will block the radio frequency vibrations. The existence of these properties, diode types are used for switches.

Zener diode is a diode which has the property that rollovers are very stable voltage, this voltage is called the zener voltage. Above the zener voltage, this diode will deliver electricity in two directions. This diode is used as a voltage stabilizer or voltage regulator. These diodes form a diode as usual, the difference can be seen only from the type that is written on bodynya and zener voltage seen at vademicum.
Resistors

In the market there are different types of resistors, can be classified into two kinds of fixed resistors is the resistor value detainees remains and anyone can diaturatur by hand, there is also a change in the value of prisoners is set automatically by light or by temperature.

Resistor color code is usually written in roundabout budaran shaped bracelet or can be color. The units used are OHM (Ω). Unless the amount of resistance, a resistor is characterized by tolerance, also written in the form of bands of color after the sign of resistance.

The next parameter is the magnitude of the resistor the maximum power allowed to pass through. Regarding the maximum power is not supplied by the manufacturer's mark but only seen from demensinya only. Resistors there who have the ability 1 / 8 Watt, 1 / 4 Watt, 1 / 2 Watt, 1 Watt, 2 Watt, 5 Watt, and so on.

The color code for tolerance is is as follows:

1 percent = Chocolate
2 percent = Red
5 percent = Gold
10 percent = Silver

Material for wire-wound resistors may be used or can be prisoners with carbon. With the coil wire resistance, then, unless the resistance, inductance will also give you a little. At this time the use of carbon resistors are not widely available in the market.
Variable Resistor (VR)

Resistor value of this type can be set by hand, if arrangements can be made at any time by the operator (there is a key regulator) is called a potentiometer and an arrangement made with a screwdriver called a trimmer potentiometer (trimpot). Prisoners in the potentiometer can be made from carbon and there are also made from coils of wire called a wirewound potentiometer. For use in high voltage usually preferred wirewound types.
Sensitive Resistor Temperature and Light Sensitive Resistors

Thermistor resistance value depends on the temperature. There are two types of NTC (negative temperature coefficient) and PTC (positive temperature coefficient). NTC little resistance when hot and cold getting bigger. Instead PTC little resistance when cold and expand when hot.

Voltage Impulses

2011-12-25T04:18:00.000-08:00

Forms of Voltage Impulses

There are three forms inpuls voltage that may be experienced in the electric power system, namely:
1. Lightning impulse voltage
2. Surge impulse voltage circuit
3. Truncated impulse voltage

Wavefronts are part of a wave that starts from point zero (nominal) to the point of peak (according to IEC determined from the nominal point of intersection between the axis of time with the straight line connecting the 30% and 90% of peak voltage). While the tail is part of the wave peak to wave down 50% from the peak point. The wave form is expressed as:
± (x Tt Tf) ms. [IEC: ± (1.2 x 50) ms]

Circuit used for surge value:
[IEC: ± (250 x 2500) ms]
Tools that can be used to generate a high voltage impulse among others:
1. RC impulse generators
2. Impulse generator RLC
3. Marx Generator
2.
5. How to Measure Voltage Impulse

a. Using Sela Ball

Sela ball is often used to measure the impulse voltage. Sela ball must always ditera with voltage spark between the ball 50% of the standard. Sela standard ball is a ball broke in qualifying standards regarding:
1. Quality
2. The distance between
3. The size of the ball

In certain circumstances the air, between the ball always has a certain spark voltage as well. That is why the sidelines ball can be used as a measuring tool.

Form of the condition of the ball electrode
Terms:
1. Its surface is slippery
2. Flat arches
3. The surface of the ball must be free of dust, oil, etc.
4. Prisoners damper installed in series with the minimum distance 2d
(D = diameter) of the ball is measured from the point where there is a spark.
a. The test voltage ac = 100 kW s / d 1000 kW
b. Impulse test voltage 500 W

b. Using a CRO

By using Chatode-Ray Oscillograph (CRO) we can:
- Voltage peak
- Waveform
- The lack of impulse shape abnormalities (describing damage to test equipment)
CRO can only measure a low voltage only, so to measure the high voltage required voltage divider (either resistors or capacitors)

switching power supply

2011-12-25T02:07:00.000-08:00

C1, 2 : 100nF, 250VAC polypropylene (RS 190-8539)
C3 : 680uF, 450V electrolytic
C4, 5, 6, 7, 8, 9, 10, 11 : 470nF, 630V polypropylene
C12, 13 : 1uF, 50V ceramic multilayer (RS 126-067)
C14 : 3.3nF, 1.6kV polypropylene
C15, 16 : 10nF, 250VAC polypropylene (RS 190-8472)
C17, 18, 19, 20, 21, 22 : 1000uF, 25V low ESR electrolytic (RS 105-997)
C23, 24 : 2200uF, 16V low ESR electrolytic (RS105-947)
C25, 26, 27, 28, 29, 30 : 100nF, 50V ceramic
C31 : 470nF, 50V ceramic multilayer
C32 : 22uF, 50V electrolytic
C33 : 10uF, 50V electrolytic
C34 : 1uF, 50V electrolytic
C35 : 33nF, 50V polyester
C36 : 4.7nF, 50V polyester
C37 : 330nF, 50V polyester or ceramic multilayer
C38 : 100uF, 10V electrolytic
D1 : Rectifier bridge, 1kV, 8A. GBPC810 or similiar.
D2, 4, 17 : Ultrafast diode, 1kV, 1A. UF4007 or similiar. Lower
voltage (down to 100V) is acceptable.
D3, 5 : Ultrafast diode 1kV, 3A. UF5408 or similiar.
D6, 7, 8, 9 : Dual Schottky diode, 100V, 30A total. PBYR30100CT
or similiar. Single diode would also be suitable.
D10, 11, 12, 13, 14, 15, 16, 18 : 1N4148 switching diode
FB1, 2 : Amidon FB-73-801 ferrite bead, slipped over wire.
FB3..14 : Amidon FB-73-2401 ferrite beads, slipped six each
over the two 13.8VDC output cables.
L1 : Common mode choke, 8mH each winding, 6A.
I used junk box specimen. RS 288-159 is suitable.
L2: : 20uH, 60A choke. 15 turns on Amidon T-157-26
toroid. Wound with ten #16 enameled wires
in parallel.
L3: : 5uH (uncritical), 60A choke. 10 turns on ferrite solenoid,
10mm diameter, 50mm long. Wound with two #11
wires in parallel.
LED1 : Dual LED, green-red, common cathode
M1 : 12V 5W brushless DC fan, 120 x 120 x 25mm
NTC1, 2 : Inrush current limiter, 2.5R cold resistance (RS 191-2005)
P1 : CEE-22 male connector with integrated fuse holder
and EMI filter, 250VAC, 6A, (RS 210-291)
Q1, 2 : High voltage switching transistor, BUH1215 or similiar.
Must resist at least 400Vceo , and maintain a
beta of over 12 at a current level of 8A. (RS 859-874)
Q3, 4 : BC639-16 transistor. Must resist 100V and 0.5A.
Q5 : BD683 darlington transistor
R1, 5 : 10R, 5W low inductance preferred
R2, 6 : 180kR, 0.5W carbon
R3, 7, 19 : 1R, 1W carbon
R4, 8 : 2,7kR, 0.25W carbon
R9 : 47R, 5W low inductance preferred (induktansi rendah)
R10, 11 : 1.8R, 2W low inductance preferred (induktansi rendah)
R12 : 180R, 0.5W carbon
R13 : 3.3kR, 0.25W carbon
R14 : 1.5kR, 0.5W carbon
R15, 16 : 3.9kR, 0.25W carbon
R17, 18, 32, 33, 36, 38 : 1kR, 0.25W carbon
R20 : 22R, 0.5W carbon
R21, 22, 23, 24 : 4.7kR, 0.25W carbon
R25, 27, 29 : 22kR, 0.25W carbon
R26 : 4.3kR, 0.25W carbon
R28 : 13kR, 0.25W carbon
R30 : 12kR, 0.25W carbon
R31 : 10kR, 0.25W carbon
R34 : 1MR, 0.25W carbon
R35, 37 : 27kR, 0.25W carbon
R39 : 33R, 2W carbon
SW1 : 2-pole power switch, 250VAC, 10A
T1 : Primary 15 turns, secondary 2+2 turns. Wound with
copper foil and mylar sheet. Uses four Amidon
EA-77-625 ferrite E-cores (8 halves). Equivalents
include Thomson GER42x21x15A, Phillips 768E608,
TDK EE42/42/15. See text for winding instructions.
T2 : Secondary is 100+100 turns #36 enamel wire. Primary
is one turn #15 plastic insulated cable, wound on
secondary. Wound on Amidon EE24-25-B bobbin. Uses an
Amidon EA-77-250 core. Equivalents are Thomson
GER25x10x6, Phillips 812E25Q, TDK EE25/19.
T3 : Control winding is 26+26 turns #27 enamel wire.
Base windings are 8 turns #20 each. Collector winding
is one turn #15 plastic insulated cable. Bobbin and
core like T2. See text.
U1 : Pulse width modulator IC, LM3524, SG3524, UC3524 or
similiar.
U2 : Quad single supply operational amplifier, LM324
or similar.
U3 : 5V voltage reference, LM336Z-5.0 or similiar.
VR1, 2, 3 : 1kR PCB mounted trimpot

Project design switching power supply has a very large power capability. This power supply produces 13.8V output, the continuous load currents up to 40A. If the potentiometers are set, then the power supply can deliver up to 60A .. Ripple voltage at the output is about 20mV, and its efficiency is 88%. A cooling fan operates depending on the time-average power used, and the LED indicator to tell if the voltage is normal, too high or too low. And Power Supply that has great power kamampuan is just a small form in the box that measures just 306 x 150 x 130mm, including all projections, and weighs only 2.8kg!

Description of Series
Line voltage through CEE-22 connector through the fuse and EMI filter (P1). Then passed through a 2-pole power switch, and again through the line filter to remove noise (C1, L1, C2). Two NTC resistors limit the inrush. A bridge rectifier provides power to large electrolytic capacitor (C3), who works at 300VDC. Power oscillator formed by Q1, Q2, and by beberaa other components, and feedback and control transformer (T3). T2 and related components act as the primary current sensors. T1 is the power transformer, providing about 20 Volt Schottky rectifier wave into the box (D6. 9). A toroidal inductor (L2) and six elekrtolit parallel capacitors provide a low resistance value equivalent forms of the main filter, while the L3 and C23 .. 24 is just there to reduce the additional riple. 13.8V is connected to the output through a series of ferrite beat with some small decoupling capacitors are mounted directly on the output terminals.
Control circuit is IC 3524 (U1), driven by the auxiliary rectifier (D17). This IC contains a voltage reference, oscillator, pulse width modulator (PWM), an error amplifier, current sense amplifier, flip-flop and the driver circuit. The sensor output voltage and current level sensors, through transistors Q3 and Q4 controls the power oscillator. C37, C35 and R23 are used to implement PID (proportional-integral-derivative) control loop response in full.
A quadruple operational amplifier (U2) is used for two purposes aids: To control the cooling fan according to the average level of current, voltage and LED indicators for steering three colors: green light if the voltage is OK, orange if the voltage is too low and the red if too high.

TOSHIBA Bipolar

2011-12-22T18:35:00.000-08:00

• TOSHIBA Bipolar Digital Integrated Circuit Silicon Monolithic
• General-Purpose Linear ICs
• 7-ch Darlington Sink Driver
• Darlington Drivers IC
• The ULN2004APG/AFWG Series are high−voltage, high−current darlington drivers comprised of seven NPN darlington pairs. All units feature integral clamp diodes for switching inductive loads. Applications include relay, hammer, lamp and display (LED) drivers. The suffix (G) appended to the part number represents a Lead (Pb)-Free product.
• Features: [1] Output current(single output): 500mA(max). [2] High sustaining voltage output: 50V(min). [3] Output clamp diodes. [4] Inputs compatible with various types of logic. [5] Package Type-APG: DIP-16pin. [6] Package Type-AFWG: SOL-16pin.
• Output Sustaining Voltage(VCE)(sus): 50V
• Output Current(Iout): 500mA
• Recommended Input Voltage: 6V to 15V
• Clamp Diode Reverse Voltage(VR): 50V
• Clamp Diode Forward Current(IF): 500mA
• Input Base Resistor: 10.5kΩ
• Number of Drivers / Receivers: 7 / 0
• Linear ICs Type: Darlington Transistor Array
• Number of Arrays: 7
• Transistor Polarity: NPN
• Input Compatibility: PMOS, CMOS
• Operating Temperature Range(Topr): -40°C to +85°C
• Storage Temperature Range(Tstg): -55°C to +150°C
• Brand Name: TOSHIBA
• Lead-Free Type
• RoHS Compliant
• Mounting Type: Through Hole / DIP(Dual in -line package)
• Package Type: DIP16
• Lead Count: 16
• Packing: 25 units / tube
• Mass stock on-hand merchandise supply
• We supply various electronic components and welcome your inquiries

power supply outage

2011-11-17T17:50:00.000-08:00

When the main power supply outage (PLN), the electricity supply required reserves and the conditions of the Generator-Set is expected to supply power mainly to priority loads. Generator can be used as a backup electrical system or "off-grid" (which depends on the resources the user needs). Generators are often used by hospitals and industries that require a steady source of power and reliable (high level of supply reliability), and also for rural areas that do not have access to commercially supplied electricity through the existing distribution network PLN.

A diesel engine generator set consists of:
1. Prime mover or mover first, in this case diesel engine (in English is called diesel engines)
2. Generator
3. AMF (Automatic Main Failure) and ATS (Automatic Transfer Switch)
4. Battery and Battery Charger
5. Panel ACOS (Automatic Change Over Switch)
6. Security for Equipment
7. Installing the Power Supplies

Diesel engine

Including diesel engines with internal combustion engines or motor fuel referred to, in terms of how to obtain thermal energy (heat energy). To generate electricity, a diesel engine connected to a generator in one axis (the axis of diesel engine is coupled with shaft generator).

An advantage of using diesel engines as a first mover:
* Design and installation is simple
* Auxilary equipment (auxiliary equipment) simple
* When loading a relatively short

Losses use diesel engines as early Mover:
* Weight machines are very heavy because it must be able to withstand vibration and high compression.
* Starting the initial weight, because the compression height is about 200 bar.
* The greater the power the diesel engine is the greater dimension, it causes trouble if the engine power is very large.
* Fuel consumption using fuel oil relatively more expensive compared to power plants that use fuels other types, such as gas and coal.

How it Works Diesel Engine

Prime mover or early mover is a device that functions produce mechanical energy required to rotate the generator rotor. In the diesel engine / diesel engine ignition occurs alone, because the process works based on pure compressed air in the cylinder at high pressure (± 30 atm), so that the temperature inside the cylinder rises. And at that time the fuel is sprayed in the cylinder-temperature and high pressure beyond the flash point fuel injected so that the fuel will burn automatically. The addition of heat or energy is always performed at a constant pressure.

Pressure of gases of combustion of fuel and air will push the piston which is connected to the crankshaft using a piston rod, so that the piston can move back and forth (reciprocating). Back and forth motion of the piston is converted into rotational motion by crank shaft (crank shaft). And contrary motion of the crankshaft rotational motion is also converted into alternating piston on the compression stroke.

Based on analyzing how the system works, diesel motors can be divided into two, namely diesel motors that use airless injection system (solid injection) were analyzed with a dual cycle and diesel motor that uses a water injection system is analyzed with the diesel cycle (while motor gasoline was analyzed by
otto cycle).

The difference between diesel and motor gasoline motor is noticeable is located on the fuel combustion process, the combustion of gasoline motor fuel is due to the fire jumps the electricity generated by two-electrode spark plug (spark plug), while the diesel engine combustion occurs due to a rise in temperature the mixture air and fuel due to compression of the piston until it reaches the flame temperature. Because the principle of pressure due to ignition of the fuel then the motor is also called a compression ignition diesel engine while the motor is called spark ignition gasoline engine.

In diesel engines, piston perform two short steps towards the cylinder head on every step of the power.
1. The first step upwards a step entry and exploitation, here the air and fuel into the crank shaft while spinning down.
2. The second step is a compression step, continue rotating the crankshaft causes the piston to rise and push the fuel, causing combustion. Both of these processes (1 and 2) including the combustion process.
3. The third step is a step expansion and work, here the two suction valves and exhaust valves are closed while the crankshaft continues to rotate and retract the piston downward.
4. The fourth step is the removal step, here the exhaust valve opens and causes the gas due to combustion of residual waste out. Gas can be due out in the fourth process is moving up the piston back up and cause the gas to exit. These two latter processes (3 and 4) including the disposal process.
5. After the fourth process, then the next process will repeat the first process, where air and fuel re-entry.

Based on the above process then the speed diesel engines can be classified into 3 parts, namely:
1. Low-speed diesel (<400 rpm) 2. Medium speed diesel (400 - 1000 rpm) 3. High speed diesel (> 1000 rpm)

Starting the system or process to turn on / run diesel engines are divided into three kinds of starting the system, namely:

1. Start System Manual
The system is used to start diesel engine with a relatively small engine power is <30 PK. The way to revive a diesel engine on this system is to use the drive crank start on the crankshaft or connecting shaft to be moved by human power. So start the system is highly dependent on human factors as the operator. 2. Electric Start System This system is used by diesel engines that have power are the <500 PK. This system uses a DC motor with power supplied by the battery / batteries 12 or 24 volts to start the diesel. At the start, the DC motor gets power supply from the battery or batteries and produces torque used to drive a diesel until it reaches a certain round. The battery or batteries used must be used to start the 6 times without recharged, since the required startup current DC motor is large enough so worn armature that serves as a DC generator. Recharging the battery or batteries used tool of a battery charger and belt tension. At the time diesel battery charger does not work then get a supply of electricity, while at work then the supply of diesel battery charger obtained from the generator. The function of the voltage security is to monitor the battery voltage or battery. Therefore, when the voltage of the battery or the battery has reached the 12/24 volts, which is the default voltage, then the relationship between the battery charger to the battery or batteries will be disconnected by a safety voltage. 3. Start the system Compression Start system is used by the diesel that has a great power that is> 500 PK. These systems use motors with high-pressure air to the start of the diesel engine. How it works is by storing a bottle of air into the air. Then the air is compressed so that the hot air and diesel fuel is inserted into the Fuel Injection Pump and sprayed through a nozzle at high pressure. The result will occur foggy and combustion in the combustion chamber. At the time the pressure in the tube down to the minimum limit, then the compressor will automatically raise the air pressure inside the tube until the pressure in the tube sufficient and ready for use to perform starting diesel engines.

power for energy

2011-11-13T18:23:00.000-08:00

Model: LDR, WDR
Capacity: 8-4000kg/h
Steam pressure: 4-16bar
Fuel: Electric

Fuel: Electric
User:
For food processing, printing and dyeing, pharmaceutical provide for production of gasoline and medical institutions with the provision of disinfection gas, for other enterprises, hotels provide the heating steam, can also provide domestic hot water heating tanks.

Features
Electric heating boiler to power for energy, no noise, no pollution. The use of high-quality heating tubes, the surface of the low heat load, heat and high efficiency. The use of multi-storey high-level centrifugal glass wool insulation, import color outer panels; Both ends covered the use of packaging in vivo to facilitate the installation of maintenance.

1, the use of advanced electric heating tubes, the surface low load, long life.
2, the boiler to start, stop, fast, wide range of load-conditioning to regulate the speed and easy to operate.
3, heating elements in accordance with changes in temperature and automatically adjust the load control input heating group number, and automatically converted into the order, not only to save energy consumption, but also control the operation of each heating time balance, so even the life of the heating tube.
4, heating elements can also be manually input or stop, user-friendly and flexible adjustment of the boiler heat.
5, the use of advanced computer boiler controller, with reliable performance, high degree of automation is easy.
6, using boiler accessories, domestic and foreign products are selected and tested by the test furnace to ensure the long-term normal operation of the boiler.

Protection device
(A), function
1, patented technology, automatic sewage functions: On the water control system for real-time detection of ion concentration, when the concentration exceeds a set value, the solenoid valve automatically open sewage, sewage automatically, start the infusion of new water pumps, heating surface so that scaling is not easy. 2, the water level real-time monitoring function: Equipped with electronic water level detection device, real-time monitoring of boiler water level.
3, the time set function: Users can be set to stop the time from the boiler.
4, before and after outsourcing are covered in vivo, the replacement of the heating pipe maintenance operation more convenient and more efficient.
(B), the protection of
1, proprietary technology, scale detection devices: The furnace once the standard scale, the system will alarm
2, leakage protection: Control system to detect leakage electric heating elements will automatically cut off power supply.
3, water protection: When the boiler water and timely control circuits cut off the heating to prevent the occurrence of dry heating pipe damaged, dry warning issued at the same time the controller instructions.
4, power protection function abnormalities: An immediate cessation of operation of the boiler.
5, overpressure protection chain: The boiler pressure exceeds a set value, and to prohibit the heater alarm.
6, over-current protection: When the boiler overload (high voltage) work, leakage circuit breaker disconnect automatically.

voltage regulator diode

2011-11-08T04:00:00.000-08:00

Zener diode is applied in the reverse breakdown of the surface contact area of the special type of silicon diode. Zener diode volt-ampere characteristic curve and silicon diode volt-ampere characteristic curves exactly the same. Zener diode characteristic curve similar to ordinary, but the reverse diode voltage curve relatively steep. Normal operating range of the diode voltage, current characteristic in the reverse current on the sudden rise in the beginning part. This section of the current, commonly used for the regulator in terms of low power, typically a few milliamperes to tens of milliamps.
The main parameters of the diode voltage regulator
(1) stable voltage Vz: stable voltage regulator diode is in normal operation, the voltage across the tube. This value with the operating current and temperature changes slightly different, both the same type of Zener diode, voltage stability has some dispersion, for example, the stability of 2CW14 silicon diode voltage regulator 6 ~ 7.5V.
(2) dissipation PM: reverse current through the PN junction diode regulator, we should have some power loss, PN junction's temperature will rise. PN junction under the permissible operating temperature determine the power dissipated in the tube. Low power tube is usually about a few hundred milliwatts to several watts.
Maximum power dissipation PZM: a regulator of the maximum power dissipation depends on the PN junction area and cooling conditions. Reverse work, PN junction power loss: PZ = VZ * IZ, and VZ by the PZM can decide IZmax.
(3) Stable current IZ, the minimum stable current IZmin, large and stable current IZmax steady current: working voltage equal to the voltage stability of the reverse current; minimum stable current: voltage regulator diode in the steady reverse current minimum required; maximum stable current: Zener diode allows the maximum reverse current.
(4) dynamic resistance rZ: the concept and the same general dynamic resistance of the diode, but the dynamic resistance of diode voltage regulator is to strike it on the reverse characteristics of the. rZ smaller, reflecting the breakdown characteristics of the regulator more steep.
rz = â–³ VZ / â–³ IZ
(5) stable voltage temperature coefficient: VZ temperature change will change in the regulator, when | VZ |> 7 V when, VZ has a positive temperature coefficient, the reverse breakdown is the avalanche breakdown.
When | VZ | <4V time, VZ has a negative temperature coefficient, the reverse is the zener breakdown.
When 4V <| VZ | <7V time, the regulator can get close to the zero temperature coefficient. This regulator diode can be used as a standard regulator.
Zener diode test
(1) positive and negative electrodes of the judge from the appearance point of view, the metal package Zener diode cathode tube-shaped end of the plane, the negative side for the semi-circular surface shape. Plastic tube regulator diode color markers printed on one end of the anode and the other end is positive. Zener diode is not clear on the signs, you can also judge the polarity with a multimeter, measure the same way with ordinary diodes, that is, R Ã— 1k file with a multimeter, then the two table T are the two electrode voltage regulator diode, a measured results, and then swap the two table T were measured. In the two measurements, the resistance that a small, black pen then the table is the positive regulator diode, the red pen then a negative regulator diode.
If the measured voltage regulator diode, the reverse resistance are very small or are infinite, then the breakdown of the diode is open or damaged.
(2) the value of the measurement of voltage 0 ~ 30V continuously adjustable DC power supply for the 13V zener diodes below, can be transferred to the output voltage of power supply 15V, the positive power series with a 1.5kÎ© current limiting resistor measured after the negative regulator diode connected to the power negative and positive phase voltage regulator diode, then both ends of the multimeter to measure voltage regulator diode, the measured reading is the voltage regulator diode value. If the regulator regulator diode is higher than 15V, the power supply should be adjusted to 20V or more.
Also be lower than the Megohmmeter 1000V diodes for testing power for the regulator. The methods were: the positive terminal of the megger negative phase with the voltage regulator diode, the negative terminal megger the positive phase with the voltage regulator diode, the required uniform shaking megger handle, while monitoring the voltage with a multimeter voltage across the diode (multimeter, as the stability of the voltage profile should be the size of the voltage) until the meter indicates the voltage stability of the instructions, this voltage is stable voltage regulator diode.
If the measurement of the stability of the diode voltage regulator fluctuated, then the instability of the diode.
Application of voltage regulator diode
Regulator used in the rectifier filter circuit, the DC output voltage to stabilize the small power supply devices.
Selection of regulator diode
Zener diode is generally used in power supply as a reference or used in over-voltage protection circuit for protection diodes.
Zener diode selected should meet the application requirements of the main parameters of the circuit. The stability of the voltage regulator diode and application should be the same value as the reference voltage circuit, the maximum stable current regulator diode application circuit should be higher than the maximum load current 50%.
Substitution regulator diode
Zener diode is damaged, should be regulated the same model the same electrical parameters of diodes or Zener diodes to be replaced.
Stability can be used with the same high-voltage power dissipation zener diodes to substitution of low power dissipation zener diodes, but not with lower power dissipation zener diodes to substitution of high power dissipation zener diodes. For example, 0.5W, 6.2V zener diodes can be 1W, 6.2V voltage regulator diode replacement.

PIC microcontroller

2011-11-07T03:29:00.000-08:00

PIC microcontroller provides a different combination of features, thus the most suitable can be selected for any given application. Some of the main selection criteria are:

•number of I/O pins availbale
•program memory size
•program memory type (ROM, EPROM, Flash)
•EEPROM data memory
•timers (8-bit or 16-bit), CCP
•interrupt sources
•analog inputs (8-bit or 10-bit)
•serial communication interfaces (USART, SPI, I2C, CAN)
•internal oscillator
•in-circuit debugging
•package (DIP, SOIC, PLCC, QFP)
•price

When developing an embedded system, the number and type of inputs and outputs need to be determined. After the hardware requirements have been established, the program need to be written and tested. Once the size of the program known, the chip memory size can be determined.

Gel permeation chromatography

2011-11-06T22:39:00.000-08:00

Gel permeation chromatography (GPC) involves steric separation of a sample, i.e., separation on the basis of size. Different detectors are used to analyze the resulting size fractions in order to quantify molecular weight and distribution, molecular size, and intrinsic viscosity. UV detection is used routinely to identify chemically different species as they elute. This is especially valuable for the analysis of copolymers and in the development of smart materials, since unique electrical, thermal, or photochromic properties often correlate directly with UV absorption characteristics. The difference in absorption profiles between polymers with similar molecular weights, refractive index increments, viscosities, or hydrodynamic radii can be significant; thus a UV detector can often differentiate when others cannot. However, a conventional system measures spectra only at a single, predetermined wavelength in the UV-VIS range. This limitation is overcome with the photodiode array (PDA) detector (Figure 1) for the TDAMax instrument (Viscotek Corp., A Malvern Company, Houston, TX).

The instrument is a comprehensive GPC system with an integrated triple or tetra detector array that includes low-angle light scattering, a differential refractive index detector, and a four-capillary differential viscometer. The PDA consists of 256 diodes and simultaneously collects data at wavelengths in the range 190–500 nm. With typical measurement times in the 20–40 min range producing a very data-rich analysis, the technique is extremely productive.

The UV cell of the PDA sits in the temperature-controlled zone of the system, which operates at temperatures up to 80 °C. A fiber-optic link to the PDA and then onto the powerful OmniSEC™ software package enables the captured data to be displayed as information-rich, easy-to-interpret 3-D images that provide insight into the nature of the sample being analyzed.

The PDA measures the complete absorption spectrum of the sample eluting at every time slice of the chromatogram, giving a fingerprint of each component in the matrix. Because it captures data across the UV-VIS range, the user does not need to select the wavelength of interest before measurement. This makes it much easier to carry out more open-ended investigative analysis into a complex polymerization reaction or when examining material about which little is known.

The software package is equally important since it simplifies data manipulation and presentation while controlling the chromatography. Looking at the full absorption spectra for each “slice” makes it easy to see what components— monomers, oligomers, different polymeric species—are eluting, giving information about molecular size and structure.

micromanipulators

2011-11-06T18:14:00.000-08:00

Crystal manipulation and harvesting have been done manually since the science of crystallography began. While the looping of larger crystals comes easily for some people, others never seem to get the knack. Some of the problems with manually harvesting crystals (both small and macro) include:
Crystals are being harvested at earlier and earlier points in their growth cycle, sometimes when they are as small as 2–5 μm. As the crystals get smaller, the ability to manually harvest them becomes more difficult.
Manual harvesting may damage the crystals due to the user’s inability to precisely control the looping tools.
When harvesting manually, higher levels of magnification required for small crystals are difficult to use because the user’s hand motions (i.e., shaking) are intensified, distorting vision and thereby affecting the ability to accurately harvest.
It is difficult to choose a specific crystal to loop since manual looping disturbs the entire drop and any other crystals that are present in that drop
Manual harvesting of crystals is done with one loop; the use of two loops simultaneously to capture crystals is rarely done by hand.

Typically, the user places a coverslip or another vessel containing the crystals under the microscope. Because time is usually limited (especially in the case of protein crystals), the user presses a single key, and the system positions the loop(s), crystals, and microscope in preparation for harvesting crystals. (Note: Sometimes a small amount of Paratone-N oil [HamptonResearch, Aliso Viejo, CA] is used to delay the dehydration of the drop holding the crystals to allow more time for harvesting.)

If the user has already selected the crystal to harvest, he/she can choose that crystal by clicking on it with the mouse. Once the desired crystal is selected, the user can harvest it manually or invoke a macro, which will harvest it automatically based on methods and training established by the user. Although several off-the-shelf macros for crystal harvesting are included with the system, the user can program in his/her own style of harvesting, with the system mimicking the user’s every move. The programmable macros control all devices available in the automated system (XYZ stage, micromanipulators, zoom, focus, etc.), as well as all software functions such as image analysis, image capture, video capture, and Z-stacked imaging.

Because the Harvester-3D can be operated remotely, it is well suited for harvesting oxygen-sensitive crystals within a glove box and offers various other benefits when used in an oxygen-free environment. For example, with its precise joystick operation, users do not have to work with gloved hands, which is a tedious, tiring, and time-consuming method of harvesting crystals.

The micromanipulators can hold either traditional loops (MiTeGen) or other types of harvesting devices, such as the Crystal Catcher. The Crystal Catcher can be programmed to automatically harvest both protein and small-molecule crystals using its polymer-based adhesive technology, and the penlike device mounts easily onto the micromanipulators.

A typical macro for harvesting crystals is as follows:
Step 1—Move stage to harvesting position. This brings the XYZ stage into position, autofocuses the microscope, and moves the micromanipulators with loops into position.
Step 2—Mark crystal(s) for harvesting. This highlights all of the crystals to be harvested (either automatically or manually).
Step 3—Begin harvesting. Depending on whether small- or macromolecule crystals are being harvested, the procedure is slightly different. For the purposes of this discussion, we will assume small-molecule harvesting is being done using UV-curable glue to attach the crystals to the mounts.

In turn, the system will:

a) Move to the UV glue position

b) Pick up a small amount of UV glue (amount predetermined by the user)

c) Move to the first crystal to be harvested

d) Pick up the first crystal using XYZ coordinates generated when the user marked the crystal (step 2)

e) Move to UV curing light for 20+ sec to harden the glue. The user can move the micromanipulator to neutral position and pause so that he or she (or the automated arm [i.e., Hitachi, Tokyo, Japan]) can remove the harvested crystal and replace the holder for the next crystal to be harvested.

bridge rectifier

2011-11-02T06:54:00.000-07:00

There are basically two versions of the P3a: a 60W into 8 ohms (with ± 35V supply rails) and a 100W into 8 ohms (with ± 42V supply rails). I decided to build the version ± 35V, for two reasons. A 60W, which is more than enough. The other is that the version is ± 42V can not drive 4 ohm speakers. I wanted the option of driving 4 ohm speakers, so the choice was easy. A ± 35V, it can be 60W at 8 ohms and 100W into 4 ohms drive.
2.2. Transistors

The transistors recommended are not available here, so I went for one of the previous recommendations. For the output transistors, I used MJ15003 and MJ15004. Used for the three drivers that I have is two BD140 (a class-A driver and an output driver) and BD139 (the other output driver).

The power supply consists of a 625 VA 25-0-25 transformer, a bridge rectifier 35A and 4 x 10,000 uF capacitors. This seems excessive, and may for all practical purposes, but which is theoretically necessary to four 100W (4 ohms) amplifier lead to an efficiency of about 70%.

The power supply requires heavy use of a starter, for which I used P39 Rod Elliott. I chose the ballast resistors so that their maximum current is used up to 200% of the transformer. In this way, the main fuse will blow, even if there is anything wrong with the transformer. Also, I attached a thermal fuse, resistors on a piece of aluminum and epoxy resin heat for added security.

As always, an amplifier is not complete without a DC protection, and I have included Rod Elliott P33 for that. See my article DC protector subwoofer for more information on this particular circuit.

I am very satisfied with the performance. But I think to do, amplifier does not affect the sound quality through a lot (as they are a decent design), and therefore I must not expect much difference with my previous (what receiver Kenwood 1978 ). Aspects that are the most visible things such as noise and the level of snoring, which are very good. There is a very very very slight hum in the speakers, but you have to press your ear against the speaker to hear it. There, I found this part of the inherent hum P3a is design, so there’s not much I can do about it, both in regard to the wiring or the power supply configuration. But because it is so marginal, it does not matter. At the end of the amplifier is exactly what I needed to, and performs accordingly.

Mini-micro hydropower

2011-10-29T22:13:00.000-07:00

Quintessence
The flow of water that flows from the highlands towards the more lace has a potential energy that can be utilized as a source of new energy. With good planning strategy for the development of energy sources such as this in turn will be able to overcome the problem of energy crisis in various places. But due to lack of planning several projects in the strategy development of alternative energy sources has not been obtained optimal benefits. often Power Plant construction project Mini-micro hydropower (MHP) there are various constraints such as low load factor, Surveying incomplete data availability and the lack of participation of surrounding communities, this led to the expected benefits from the potential of renewable energy sources has not been optimal. Therefore it needs a presence of an improvement.

Power micro hydro power

Generating a mini-micro hydro power plants are basically constructed in order to program the Village Electrical Sign (LISDES) with the utilization of hydropower resources. The construction project is primarily directed to remote areas unreachable grid. Generation is done by utilizing the flow of water from the tributaries are small or of irrigation channels. One of the factors that draw power from the mini-micro hydro is a relatively simple technology. However, if the feasibility study before the implementation of development projects is not adequate then the consequences become less efficient operation of the generation can not even operate at all.

Micro hydro is a generator that can generate electrical energy up to 100 KW while for a power plant that can produce electrical energy equal to 100 KW - 5 MW are defined as micro-hydro power plant. Mini-micro hydro power potential in Indonesia about 7,500 MW with an installed capacity of 200 MW. According to Central Statistics Agency (BPS) in 2000, about 60% of Indonesia's population live in remote villages. The number of villages in Indonesia as many as 58,545 villages, until the end of December 2000 which had as many as 49,155 villages have electricity.

Advantages micro hydro power plants

Some of the advantages of mini-micro hydro energy from others (Das, 2002) is:

· Clean Environment

· Renewable energy

· Not to consumptive water use

· Easy to operate as base load and peak load (can be quickly on / off)

· Cost low operating

· Durable (Long Life)

· Ideal for remote areas

Most of the mini-micro hydro development projects aimed to remote areas that have not passed by the grid. Problems develop when these arise as a result of the economical factors. Electrical energy consumption by rural communities generally ranges between 4-5 hours per day or 14-16% of installed power. The low energy consumption (load factor) is caused by the use of only as a mere illumination lamps. Economy aspects of power generation mini-micro hydro can be achieved with a careful plan by involving the participation of local communities are actively since the beginning of project development and integration of the apparatus with the village residents.

Besides generating a mini-micro hydro power plants have their own transmission and distribution network operation and management which can be referred directly to the local village board through cooperative enterprise. As an example of the success of the mini-micro hydro project in China because of high levels of electrical energy consumption by a factor of the load reaches 50-60% of installed power capacity and its management handed over to cooperatives.

Simple model intended use of electric energy produced to achieve load factors of more than 50% are as follows:

Day:

· Grinding of agricultural products

· Cooking

· Small Industries (cooling, distillation, etc.)

Afternoon Day:

· Lighting

· Home appliances

Night Day:

· Hatching eggs

· Fumigation fish

· Drying of agricultural products

Installation Type MHP

Broadly speaking MHP installation types can be grouped into two. Include the installation of mountainous areas and the installation of a flat area.

a. This type of installation for mountainous areas generally consist of the following components:

1. Door collection (Intake / Diversion)

2. Bath deposition (Desilting Tank)

3. Dissipation channel (Headrace)

4. Bak tranquilizers (Forebay)

5. Rapid pipe (penstock)

6. Building Plant (Power House)

7. Discard channel (Tailrace)

8. Transmission Network (Grid Line)

b. Installation of Flat Area

This type of installation for flat areas generally consist of the following main components:

Door collection (Intake / Diversion)

Channel Power (Power Canal)

Dissipation channel (Headrace)

Building Plant (Power House)

Discard channel (Tailrace)

Transmission Network (Grid Line)

Selection of Technology

Selection of technology in the construction of mini-micro hydro mainly lies in the selection of the main components of the turbine and generator. This is due to the area to be installed mini-micro hydro power plants have characteristics spesification.

a. type of hydropower turbine depends on the head and discharge water. For mountain areas that have low discharge height with high head turbine type is more suitable for use while in a flat area with a large discharge of water can use this type of canal drop low head turbine.

b. Types of Generators, In general there are two types of generators used in MHP, ie synchronous generators and induction generators.

Synchronous generators working on changing speeds. To be able to keep the generator speed remains, use an electronic speed governor. Generators of this type can be used directly and does not need another power grid as early movers. Highly suitable for use in remote villages with insulation systems.

Induction generators, is not required system voltage regulation and speed. However, this type of generator can not work alone because it requires an electrical grid system as early movers. Generators of this type are more suitable for areas that have been passed by the power grid (Grid System).

Conclusion

A micro hydro power projects are continuing to consider the following factors:

1. Planning in the choice of technology must be supported by concrete data, simply and can be accounted accountability.

2. The need for utilization of electrical energy for productive activities in the afternoon and evening in an optimal

3. The existence of local community participation through the establishment of proper management organization, between society and the institutions or agencies.

LM1830

2011-10-24T21:23:00.000-07:00

LM1830 based liquid level indicator circuit. LM1830 is a monolithic integrated circuit that can be used in liquid level indicator / control systems. Manufactured by National Semiconductors, the LM1830 can detect the presence or absence of polar fluids . Circuits based on this IC requires minimum number of external components and AC signal is passed through the sensing probe immersed in the fluid. Usage of AC signal for detection prevents electrolysis and this makes the probes long lasting. The IC is capable of driving a LED, high impedance tweeter or a low power relay at its output. The circuit of a low liquid level indicator with LED is shown above. Capacitor Ct sets the frequency of the internal oscillator. With the give value of C1 the frequency will be around 6KHz. Capacitor Cb couples the oscillator output to the probe and it ensures that no DC signal is applied to the probe. The circuit detects the fluid level by comparing the probe to ground resistance with the internal reference resistor Rref. When the probe to ground resistance goes above the Rref the oscillator output is coupled to the base of the internal output transistor making it conducting.

Sweep-Frequency

2011-10-24T20:56:00.000-07:00

Sweep-Frequency Generator The working of a sweep-frequency generator is explained in the article below. The working and block diagram of an electronically tuned sweep frequency generator and its different parameters are also explained. Related Article SIGNAL GENERATORS A sweep frequency generator is a type of signal generator that is used to generate a sinusoidal output. Such an output will have its frequency automatically varied or swept between two selected frequencies. One complete cycle of the frequency variation is called a sweep. depending on the design of a particular instrument, either linear or logarithmic variations can be introduced to the frequency rate. However, over the entire frequency range of the sweep, the amplitude of the signal output is designed to remain constant. Sweep-frequency generators are primarily used for measuring the responses of amplifiers, filters, and electrical components over various frequency bands. The frequency range of a sweep-frequency generator usually extends over three bands, 0.001 Hz – 100 kHz (low frequency to audio), 100 kHz – 1,500 MHz (RF range), and 1-200 GHz (microwave range). It is really a hectic task to know the performance of measurement of bandwidth over a wide frequency range with a manually tuned oscillator.

Signal Generators In this article, the detailed explanation of a signal generator is given. The principles of signal modulation, the block diagram of an AM signal generator and the measures needed to achieve a stable frequency output is explained below. RELATED ARTICLE SWEEP FREQUENCY GENERATOR Like an oscillator, a signal generator is also a source of sinusoidal signals. The main difference between a signal generator and an oscillator is that a signal generator is capable of modulating its sinusoidal output signal with other signals. When signal generators are used for producing an unmodulated sinusoidal output they are said to be producing continuous height wave [CW] signal. When the produced output signal is modulated, the modulating waveforms may be either externally applied sine-waves, square waves, triangular waves, pulses or more complex signals, as well as internally generated sine-waves. Amplitude modulation (AM) or frequency modulation (FM) may be used. Normally amplitude (AM) modulation is employed. Principles of amplitude modulation (AM) and frequency modulation (FM) are illustrated in the figure shown below. Signal Modulaton Signal Generator – Applications Signal generators are primarily employed for providing appropriate signals for calibration, testing and troubleshooting of the amplifier circuits used in communication.

IC NE555

2011-10-24T20:36:00.000-07:00

The circuit diagram of a very simple voltage doubler using NE555 timer is shown here. Here IC NE555 is wired as an astable mutivibrator operating at around 9KHz. The base of the two transistors (Q1 and Q2) is shorted and output of the astable multivibrator (pin 3) is connected to it. When the output of astable multivibrator is low, Q1 will be OFF and Q2 will be ON. The negative terminal of the capacitor C3 will be shorted to ground through T2 and it will be charged to the input supply voltage. When the output of the astable multi vibrator is high, transistor Q1 will be ON and transistor Q2 will be OFF. The capacitor C4 will be charged to the voltage across capacitor C3 plus the input supply voltage (that is double the input voltage). This is how the circuit works. This voltage doubler circuit can deliver only up to 50mA output current and above that current limit the output voltage will be dramatically reduced.

NE555 timer IC are already published here and this is just another one.Here is the circuit diagram of a police siren based on NE55 timer IC. The circuit uses two NE555 timers ICs and each of them are wired as astable multivibrators.The circuit can be powered from anything between 6 to 15V DC and is fairly loud.By connecting an additional power amplifier at the output you can further increase the loudness. IC1 is wired as a slow astable multivibrator operating at around 20Hz @ 50% duty cycle and IC2 is wired as fast astable multivibrator operating at around 600Hz.The output of first astable mutivibrator is connected to the control voltage input (pin5) of IC2. This makes the output of IC2 modulated by the output frequency of IC1, giving a siren effect. In simple words, the output frequency of IC2 is controlled by the output of IC1. Circuit diagram. Notes. The circuit can be assembled on a Perf board. I used 12V DC for powering the circuit. Instead of using two NE55 timer ICs, you can also use a single NE556 timer. NE556 is nothing but two NE555 ICs in one package.

P-N junction

2011-10-24T19:31:00.000-07:00

Zener diode is a P-N junction diode specially designed to operate in the reverse biased mode. It is acting as normal diode while forward biasing. It has a particular voltage known as break down voltage, at which the diode break downs while reverse biased. In the case of normal diodes the diode damages at the break down voltage. But Zener diode is specially designed to operate in the reverse breakdown region.

The basic principle of Zener diode is the Zener breakdown. When a diode is heavily doped, it’s depletion region will be narrow. When a high reverse voltage is applied across the junction, there will be very strong electric field at the junction. And the electron hole pair generation takes place. Thus heavy current flows. This is known as Zener break down.

So a Zener diode, in a forward biased condition acts as a normal diode. In reverse biased mode, after the break down of junction current through diode increases sharply. But the voltage across it remains constant. This principle is used in voltage regulator using Zener diodes.

Rectifier diodes

2011-10-24T19:14:00.000-07:00

Rectifier diodes are the most commonly used diode type but other diodes come into play as well. These include Zener diodes, Schottky diodes, tunnel diodes, photodiodes, varicap diodes and light-emitting diodes. Each diode type has a different function. For example, Zener diodes control voltage, Shottky diodes work in switch circuits, light-emitting diodes are in lighting and video display circuits. Photodiodes are in light-detection circuits. A "varicap" diode is constructed like a diode but behaves as a variable capacitor.

Rectifier Tesla ham

Bridge Diode Rectifier KBL406

Voltage Diode HV HF Rectifier

Recovery Diode Rectifier Stack

EM DC Amplifier

2011-10-07T22:33:00.000-07:00

EM DC Amplifier model A22 is a low noise amplifier module for sensitive DC measurements, data collection and systems, and is ideal for very sensitive temperature measurement using thermocouples.
The noise level of the A22 is equivalent to a perfect resistor of about 150 ohms.
When used with normal type thermocouples for temperature measurement, sensitivities of around 20 micro-Kelvin can be achieved. The input voltage drift is very low and is compatible with voltage sensitivities of about 1 nanovolt.
The A22 has many other features desirable in a measurement amplifier. The very high loop voltage gain of 100T, or 280dB, means that high overall gain may be used, controlled precisely by feedback resistors, thus ensuring good linearity, with the accuracy defined by the feedback resistors used.
Despite the high gain, the model A22 is stable with 100% feedback, thus allowing feedback capacitors to be used to filter the output. The input signal level can be up to plus or minus 20 milli-volts and the output can be up to plus and minus 3 volts.
The response time of the A22 is fast, and the gain is reduced to unity at about 20 kHz, thus ensuring good response times, even at high gain settings.
The power supply requirement is low, being about 1.2 milli-amps with power supplies of plus and minus 6 volts, making it ideal for multi-channel measurement systems.
The A22 is designed to be mounted on a printed circuit board, using a 0.1” grid, with 13 pin connections on a rectangle 1.6” X 1.2”, and is built into a heavy gauge mumetal case which gives it very good magnetic, electrostatic and thermal immunity from interference. A printed circuit board is available which provides connections for power supply, gain, filter capacitors and outputs. It also contains controls for voltage and current offsets, power supply de-coupling and a passive output filter to reduce any modulation by-product.

AQ4X90 Amplifier

2011-10-07T22:27:00.000-07:00

Model AQ4X90
Digital Four Channel Amp

Input Sensitivity 0.2V ~ 8V
Signal to Noise Ratio 100 <
Damping Factor 250 <
External Fuse Rating 2 x 30Amp
Tested Voltage and THD 14.4V & 1% THD
4 ohm Power 90W x 4
2 ohm Power 120W x 4
4 ohm Mono Power 240W x 2
Channel 1 and 2:

Variable X-over 45 Hz (450Hz) ~ 450Hz (4.5KHz) at 12dB/Oct.
X-over Multiply x 1, x 10
X-over Selector Clone 3/4/FULL/HPF
Channel 3 and 4:

Subsonic Filter 10~360 Hz at 12 dB/Oct.
Bass Boost 0~12 dB
Variable X-over 45 Hz (450Hz) ~ 450Hz (4.5KHz) at 12dB/Oct.
X-over Multiply x 1, x 10
X-over Selector LPF-BP /HPF-FULL
Outputs Line Out
Dimensions (mm) 350mm (L) x 238mm (W) x 59.6mm (H)
Dimensions (in) 13.78in (L) x 9.37in (W) x 2.35in (H)

XLS Series amplifiers

2011-10-07T22:12:00.000-07:00

XLS Series amplifiers are professional Stereo power amplifiers engineered to meet demanding Audio requirements - reliably and within budget. Every XLR Series Amplifier is backed by Crown's unequaled three-year, no-fault, fully transferable warranty that covers everything.

With over five decades of experience designing and building rock-solid products, Crown is the standard in Amplifier technology. So check out the affordable Crown XLS Series.

Crown CT4150 Specifications:
CHANNELS: 4
Sensitivity: 1.4V
RATED POWER OUTPUT: 125W per Channel into 8 Ohms
Signal to Noise Ratio (below rated power 20Hz to 20kHz, A-Weighted): 110dB
Total Harmonic Distortion (THD) (full rated power, 20Hz - 20kHz): < 0.05% INTERMODULAR DISTORTION (from 0dB down to -40dB): < 0.05% Frequency Response (at 1W into 4/8 Ohms): +/- 0.5dB CROSSTALK (below rated power 20Hz to 1kHz): > 70dB
COMMON MODE REJECTION (20Hz to 1kHz): > 55dB, typically > 70dB
DIMENSION (H x W x D): 1.75" x 19" x 14.25"
NET WEIGHT: 10 lbs/4.54 kg
NET SHIPPING WEIGHT: 15 lbs/6.8 kg

PWM amplifier chips

2011-10-07T22:07:00.000-07:00

PWM amplifier chips requires an analysis of performance specifications. Output current is the maximum continuous current that can be delivered in the output. Input offset voltage is the amount of DC voltage that amplifiers produce even when 0 V is applied to the input. The supply voltage range includes minimum and maximum amounts. Internal power dissipation is the maximum amount of power that can be safely supported. Quiescent current is produced during normal operation. The power bandwidth or large-signal bandwidth describes an amplifier’s ability to provide a maximum output voltage swing with increasing frequency. The peak output swing is the output voltage at the frequency which represents the upper limit of the power bandwidth. A high switching frequency allows smaller output filters to be built into the amplifier enclosure. Typically, suppliers list the switching frequency for PWM amplifier chips as a maximum amount.

PWM amplifier chips are available in a variety of integrated circuit (IC) package types and with different numbers of pins. Basic IC package types include single in-line package (SIP), dual in-line package (DIP), discrete package (DPAK), small outline package (SOP), and quad flat package (QFP). Many packaging variants are available. For example, common SOP variants include shrink small outline package (SSOP) and thin shrink small outline L-leaded package (TSSOP). Small outline integrated circuit (SOIC) packaging is also available for PWM amplifier chips. TO-3 is a transistor outline (TO) package with three leads. TO-92, another transistor outline package, is often used for low power devices. By contrast, TO-220 is suitable for high power, medium current, and fast-switching power devices.

log amp chips

2011-10-07T22:02:00.000-07:00

Logarithmic amplifier chips (log amp chips) produce an output voltage that is directly proportional to the logarithm of the input voltage. Operational amplifier chips (op amp chips) are general-purpose, closed loop devices used to implement linear functions. They compare two incoming signals and release a third that is an amplified measure of the difference between the two. Power operational amplifier (POA) chips are used to increase the power of low-level signals in applications that drive low impedances or reactive loads. Pulse width modulated (PWM) amplifier chips generate a current that switches between high and low output levels. Sample-and-hold amplifier chips freeze analog voltage instantly. During this process the HOLD command is issued and analog voltage is available for an extended period. Specialized amplifier and comparator chips are also available.

Amplifier and comparator chips differ in terms of performance specifications and available features. Specifications for differential amplifier chips include bandwidth, gain, minimum gain, supply voltage, supply current, offset voltage, slew rate, and harmonic distortion (second and third harmonics).

Features include number of leads, package type, and power-down options. Specifications for instrumentation amplifier chips include input common-mode voltage range to negative rail, rail to rail (input or output), gain, minimum stable closed loop gain, maximum supply current, maximum voltage offset, typical common mode rejection ratio, typical power supply rejection ratio, maximum input bias current, typical unity gain bandwidth, typical slew rate, input voltage noise, and input current noise.

RF amplifiers

2011-10-07T21:43:00.000-07:00

RF amplifiers requires an analysis of several performance specifications. Operating frequency is the frequency range for which RF amplifiers meet all guaranteed specifications. Design gain, the ratio of the output to the input power, is normally expressed in decibels (dB), or Gdb = 10 * log (Po/Pi). Output power is the signal power at the output of the amplifier under specified conditions such as temperature, load, voltage standing wave ratio (VSWR), and supply voltage. Gain flatness indicates the degree of the gain variation over its range of operating wavelengths. Secondary performance specifications to consider include noise figure (NF), input VSWR, output VSWR, and monolithic microwave integrated circuit (MMIC) technology. The noise figure, a measure of the amount of noise added to the signal during normal operation, is the ratio of the signal-to-noise ratio at the input of the component and the signal-to-noise ratio measured at the output. The NF value sets the lower limit of the dynamic range of the amplifier. Input VSWR and output VSWR are unit-less ratios ranging from 1 to infinity that express the amount of reflected energy.

There are several physical and electrical specifications to consider when selecting RF amplifiers. Physical specifications include package type and connector type. Package types include surface mount technology (SMT), flat pack, and through hole technology (THT). RF amplifiers may also be connectorized or use waveguide assemblies. Connector types include BNC, MCX, Mini UHF, MMCX, SMA, SMB, SMP, TNC, Type F, Type N, UHF, 1.6 / 5.6, and 7/16. Important electrical characteristics include nominal operating voltage and nominal impedance. Operating temperature is an important environmental parameter to consider.

4 ohm speaker

2011-10-07T21:27:00.000-07:00

The "50watts" part is the one we notice first and everything else qualifies how that "50watts" was measured. Having enough power is what most people look for in an amp. However, other things come into play. If the you are going to run a load less than 4 ohms, then the current capability of the amp is definitely important and most specs do not give a current capability. A power rating into 2 ohms can help though. If the power doubles into 2 ohms then you know that the amp is built strongly enough that it can deliver enough current to drive a 2 ohm load. You may think that this is not important if you are not going to drive 2 ohm loads but it is important. Speakers (woofers, midranges, tweeters, etc) are not purely resistive. They have capacitive and inductive properties as well. Depending on the music and your setup, the impedance may dip well below 4 ohms for a nominally 4 ohm speaker.
Whether you amp can supply current fast enough to reproduce the music faithfully depends partially on the amp's slew rate (how fast its output can change), its damping factor (how easily it can control the speaker) and its current capability. For these reasons 2 ohm power is important even when driving 4 ohm speakers. Slew rates of 100V/microsec and damping factors above 100 (referenced with a 4 ohm load) are good but that information is usually not given out by the amp manufacturer. I hope it is clear now that the number of watts an amp can produce is only one factor in determining whether an amp is capable of the performance you desire.
On a final note on this part of the spec, most head units use IC (integrate circuits or chips) for the built-in amp's output stage. Those chips rarely can provide adequate current which is why even most novices know not drive subwoofers from a head unit. Real amps often have ICs in them as well but the output stages are almost always discrete, meaning they are built from transistors, resistors, capacitors and not integrated together inside tiny ICs. Advances in IC technology always making them better though.

two terminals

2011-10-07T21:00:00.000-07:00

Bi-Amping refers to using different amplifiers (or different channels of the same amp) for the low and high frequencies in the same speaker. On a 3-way speaker, usually the mid and tweeter are driven by one amp, and the woofer is driven by more powerful amp. This allows you to purchase a high quality low power amp for the highs, and a more powerful amp for the lows. With the proper pre-amp you can also have more control over the bass output. On a 2-way speaker, the mid and tweeter are driven by different channels on an amp. This is usually done so that you can use an active crossover before the amplifier.
In DIY audio, bi-amping has even more advantages. Low pass crossovers for woofers require very large inductors. These inductors are basically very long coils of copper wire which can have a very high resistance. Using an active crossover before the amplifier removes the need for these inductors. Bi-amping also removes the need for any circuits to fix problems caused by different sensitivities or impedances between drivers.
If a speaker is capable of bi-amping, then the plate on the back of the speaker will have 4 binding posts: 2 + terminals and 2 - terminals. Both + terminals and both - will have a piece of metal connecting them together. To bi-amp the speaker, remove the metal piece. Then, use the top 2 terminals for the high frequency amp, and the bottom two terminals for the bass amp.
Note: some professional audio equipment has 4 binding posts on the back. This is for ease of running multiple speakers in parallel. It is not for bi-amping, and the terminals should not be connected.

Laser diodes

2011-10-04T04:42:00.000-07:00

Laser diodes are used in all areas of electronics from domestic equipment, through commercial applications to hash industrial environments. In all these applications laser diodes are able to provide a cost effective solution while being rugged and reliable and offering a high level of performance.

Laser diode technology has a number of advantages:
Power capability: Laser diodes are able to provide power levels from a few milliwatts right up to a few hundreds of watts.
Efficiency: Laser diode efficiency levels can exceed 30%, making laser diodes a particularly efficient method of generating coherent light.
Coherent light: The very nature of a laser is that it generates coherent light. This can be focussed to a diffraction limited spot for high density optical storage applications.
Rugged construction: Laser diodes are completely solid state and do not require fragile glass elements or critical set-up procedures. Accordingly they are able to operate under harsh conditions.
Compact: Laser diodes can be quite small allowing for laser diode technology to provide a very compact solution.
Variety of wavelengths: Using the latest technology and a variety of materials, laser diode technology is able to generate light over a wide spectrum. The use of blue light having a short wavelength allows for tighter focussing of the image for higher density storage.
Modulation: It is easy to modulate a laser diode, and this makes laser diode technology ideal for many high data rate communications applications. The modulation is achieved by directly modulating the drive current to the laser diode. This enables frequencies up to several GHz to be achieved for applications such as high-speed data communications.

Dual section air variable capacitor

2011-09-20T23:05:00.000-07:00

Dual section air variable capacitor

was invented to provide tracking between two related LC-tuned circuits, as in a radio receiver. Such capacitors are basically two (in the case of Fig. 5) or more variable capacitors mechanically ganged on the same rotor shaft.

In Fig. 5, both sections of the variable capacitor have the same capacitance, so they are identical to each other. If this capacitor is used in a superheterodyne radio, the section used for the local oscillator (LO) tuning must be padded with a series capacitance in order to reduce the overall capacitance. This trick is done to permit the higher-frequency LO to track with the RF amplifiers on the dial.

In many superheterodyne radios, you will find variable tuning capacitors in which one section (usually the front section) has fewer plates than the other section. One section tunes the RF amplifier of the radio, and the other tunes the local oscillator. These capacitors are sometimes called cut-plate capacitors because the LO section plates are cut to permit tracking of the LO with the RF.

Transmitting air variable capacitor

2011-09-20T22:35:00.000-07:00

Transmitting air variable capacitor

Differential variable capacitors also have two independent stators, but unlike in the butterfly capacitor where capacities on both sides increase equally as the rotor is turned, in a differential variable capacitor one section's capacity will increase while the other section's decreases, keeping the stator-to-stator capacitance constant. Differential variable capacitors can therefore be used in capacitive potentiometric circuits.

The one requirement of transmitting variable capacitors (and certain antenna tuning capacitors) is the ability to withstand high voltages. The high-power ham radio or AM broadcast transmitter will have a dc potential of 1500 to 7500 V on the RF amplifier anode, depending on the type of tube used. If amplitude-modulated,the potential can double. Also, if certain antenna defects arise, then the RF voltages in the circuit can rise quite high. As a result, the variable capacitor used in the final amplifier anode circuit must be able to withstand these potentials.
Two forms of transmitting variables are typically used in RF power amplifiers and antenna tuners. Figure 7 shows a transmitting air variable capacitor. The shaft of this particular capacitor is nylon, so it can be mounted either with the frame grounded or with the frame floating at high voltage. The other form of transmitting variable is the vacuum variable. This type of capacitor is a variation of the piston capacitor, but it has a vacuum dielectric (K factor = 1.0000). The model shown in Fig. 8 is a 18- to 1000-pF model that is driven from a 12-Vdc electric motor. Other vacuum variables are manually driven.

Vacuum variable capacitor

phase locked loop (PLL)

2011-09-20T22:13:00.000-07:00

"Digital phase-locked loop block diagram"

A phase detector compares two input signals and produces an error signal which is proportional to their phase difference. The error signal is then low-pass filtered and used to drive a VCO which creates an output phase. The output is fed through an optional divider back to the input of the system, producing a negative feedback loop. If the output phase drifts, the error signal will increase, driving the VCO phase in the opposite direction so as to reduce the error. Thus the output phase is locked to the phase at the other input. This input is called the reference.

Analog phase locked loops are generally built with an analog phase detector, low pass filter and VCO placed in a negative feedback configuration. A digital phase locked loop uses a digital phase detector; it may also have a divider in the feedback path or in the reference path, or both, in order to make the PLL's output signal frequency a rational multiple of the reference frequency. A non-integer multiple of the reference frequency can also be created by replacing the simple divide-by-N counter in the feedback path with a programmable pulse swallowing counter. This technique is usually referred to as a fractional-N synthesizer or fractional-N PLL

Typically, the reference clock enters the chip and drives a phase locked loop (PLL), which then drives the system's clock distribution. The clock distribution is usually balanced so that the clock arrives at every endpoint simultaneously. One of those endpoints is the PLL's feedback input. The function of the PLL is to compare the distributed clock to the incoming reference clock, and vary the phase and frequency of its output until the reference and feedback clocks are phase and frequency matched.

PLLs are ubiquitous—they tune clocks in systems several feet across, as well as clocks in small portions of individual chips. Sometimes the reference clock may not actually be a pure clock at all, but rather a data stream with enough transitions that the PLL is able to recover a regular clock from that stream. Sometimes the reference clock is the same frequency as the clock driven through the clock distribution, other times the distributed clock may be some rational multiple of the reference.

One desirable property of all PLLs is that the reference and feedback clock edges be brought into very close alignment. The average difference in time between the phases of the two signals when the PLL has achieved lock is called the static phase offset (also called the steady-state phase error). The variance between these phases is called tracking jitter. Ideally, the static phase offset should be zero, and the tracking jitter should be as low as possible.[dubious – discuss]

Phase noise is another type of jitter observed in PLLs, and is caused by the oscillator itself and by elements used in the oscillator's frequency control circuit. Some technologies are known to perform better than others in this regard. The best digital PLLs are constructed with emitter-coupled logic (ECL) elements, at the expense of high power consumption. To keep phase noise low in PLL circuits, it is best to avoid saturating logic families such as transistor-transistor logic (TTL) or CMOS.[citation needed]

Another desirable property of all PLLs is that the phase and frequency of the generated clock be unaffected by rapid changes in the voltages of the power and ground supply lines, as well as the voltage of the substrate on which the PLL circuits are fabricated. This is called substrate and supply noise rejection. The higher the noise rejection, the better.

To further improve the phase noise of the output, an injection locked oscillator can be employed following the VCO in the PLL.
Frequency Synthesis

In digital wireless communication systems (GSM, CDMA etc.), PLLs are used to provide the local oscillator for up-conversion during transmission and down-conversion during reception. In most cellular handsets this function has been largely integrated into a single integrated circuit to reduce the cost and size of the handset. However, due to the high performance required of base station terminals, the transmission and reception circuits are built with discrete components to achieve the levels of performance required. GSM local oscillator modules are typically built with a frequency synthesizer integrated circuit and discrete resonator VCOs.

AC contactor

2011-09-20T21:41:00.000-07:00

LC1-D series AC contactor (simplified as contactor in the following)is suitable for using in the circuits up to the rated voltage 660V AC 50Hz or 60Hz, rated current 95A, for making and breaking and frequent starting, controlling the AC motor. Combined with the auxiliary contact group, air delayer, machine interlocking device etc, it is combined into the delay contactor, mechanical interlocking contactor, dtar-delta starter, with the thermal realay, it is combined into the electromagnetic starter.

supercapacitor

2011-09-20T21:04:00.000-07:00

supercapacitor has a limited range of applications, advances in design might eventually expand the product’s utility. For example, researchers continue to develop and experiment with newer forms of dielectric materials, such as carbon nanotubes, polypyrrole, and barium titanate, which may improve capacitance and energy density. The concept of combining supercapacitors with alternative energy sources to replace car batteries has gained appeal within the current "green" movement, and several public transportation systems have created pilot trials for capacitor-run buses and trains. If these and other developments yield successful results, the electric double-layer capacitor may achieve greater functionality and gain a larger role within the energy industry.

Manufacturers evaluating various electrical sourcing options should examine the strengths and weaknesses unique to the double-layer format. A supercapacitor’s energy density ratio typically ranges between 0.5 and 10 Wh/kg (nominal voltage over weight), which is considerably higher than that of a standard capacitor. While this energy density is still relatively low compared to mainline batteries, such as the lithium-ion model, the supercapacitor’s power density far exceeds the level offered by its counterparts. Power density is contingent on a device’s rate of electrical charging and discharging, meaning that supercapacitors can both generate and distribute energy more quickly than most batteries.

In addition, supercapacitors stop charging when their capacity limit is reached, eliminating the need for detection units to prevent overcharging. Aside from its excellent power density, a supercapacitor also has high cycle efficiency and can undergo millions of charging sequences in its lifespan.

However, low energy density and low voltage tolerance limit the effectiveness of an individual double-layer capacitor as a storage unit, unless it is serially linked to a group of capacitors. Furthermore, the supercapacitor’s linear discharge method often prevents the full charge from being delivered, resulting in small but detrimental energy waste. The high rate of self-discharge (energy loss due to internal chemical reactions) is a similar concern. Supercapacitor controls and electronic switching equipment can also be complex, and typically necessitate workers with specialized operational skills.

practical capacitor

2011-09-20T20:34:00.000-07:00

A practical capacitor is not limited to two plates. As shown to the right, it is quite possible to place a number of plates in parallel and then connect alternate plates together. In addition, it is not necessary for the insulating material between plates to be air. Any insulating material will work, and some insulators have the effect of massively increasing the capacity of the resulting device to hold an electric charge. This ability is known generally as capacitance, and capacitors are rated according to their capacitance.

It is also unnecessary for the capacitor plates to be flat. Consider the figure below, which shows two "plates" of metal foil, interleaved with pieces of waxed paper (shown in yellow). This assembly can be rolled up to form a cylinder, with the edges of the foil extending from either end so they can be connected to the actual capacitor leads. The resulting package is small, light, rugged, and easy to use. It is also typically large enough to have its capacitance value printed on it numerically, although some small ones do still use color codes.

The schematic symbol for a capacitor, shown below and to the right of the rolled foil illustration, represents the two plates. The curved line specifically represents the outer foil when the capacitor is rolled into a cylinder as most of them are. This can become important when we start dealing with stray signals which might interfere with the desired behavior of a circuit (such as the "buzz" or "hum" you often hear in an AM radio when it is placed near fluorescent lighting). In these cases, the outer foil can sometimes act as a shield against such interference.

Voltage regulator serves

2011-09-18T20:31:00.007-07:00

Rectifier circuit is good enough if its voltage ripple is small, but there are stability issues. If the voltage PLN up / down, then the output voltage will also rise / fall. As rectifier circuit above, if the flow the greater the voltage dc discharge was also dropped. For some applications a voltage change is quite annoying, so it requires the active component that can regulate the output voltage becomes stable.

Voltage regulator serves as a filter voltage to suit. Therefore, usually in a series of power supply then the voltage regulator IC is always used for stable voltage outputan.

Here the composition of the regulator IC legs.

For example 7805 is a voltage regulator to get a +5 volt, +12 volt voltage regulator 7812 and beyond. While the 79XX series is the 7905 and 7912 such that a row is a voltage regulator -5 and -12 volts.

Apart from a fixed voltage regulators have a voltage regulator ICs also can be arranged. The principle is the same as the OP-amp regulator packaged in a single IC for regulators such as LM317 LM337 variable positive and negative variables for the regulator. The difference resistors R1 and R2 are outside the IC, so the output voltage can be set via external resistors.

The most simple regulator circuit shown in Figure 6. In this circuit, the zener breakdown work on the area, thus producing the same output voltage with a zener or a voltage Vout = Vi. However, this circuit is only useful if the load current not exceeding 50mA.
The principle that the power supply circuit is called a shunt regulator, one of his trademark is the component parallel to the load regulator. Another feature of the shunt regulator is susceptible to short-circuit. Notice when Vout connected short (short-circuit) then the current is fixed I = Vin/R1. In addition to a shunt regulator, there are also called series regulator. The main principle of such series regulator circuit in figure 7 below. In this circuit the output voltage is:

Vout = VZ + VBE

VBE is the base-emitter voltage of transistor Q1 which is between 0.2 - 0.7 volts depending on the type of transistor used. By ignoring the current IB flowing in the transistor base, a large resistance R2 can be calculated that is needed is:

R2 = (Vin - Vi) / Iz

Iz is the current minimum required by the zener diode to achieve the zener breakdown voltage. These large currents can be determined from the magnitude datasheet approximately 20 mA.

If necessary supply a larger current, base current IB of the calculations on the above circuit can not be ignored anymore. Where as it is known, a large flow of IC will be directly proportional to the flow defined by IB or IC = BIB. For this purpose, the transistor Q1 is used can be replaced with a Darlington transistor which typically has a value of b is large enough. With a Darlington transistor, the current small base that could produce a greater current IC.

Techniques that better regulation is to use the Op-Amp to drive a transistor Q, as in a series of figure 8. Zener diodes are not here to give direct feedback to the transistor Q, but as a reference voltage for the Op-amp IC1. Feedback on the negative pin of op-amp is an excerpt from the voltage regulator out, namely:

Vin (-) = (R2 / (R1 + R2)) Vout

If the voltage Vout rising out, the voltage Vin (-) will also be rising until the voltage is equal to the reference voltage Vi. And vice versa if the voltage Vout decreases exit, for example because of supply current to the load increases, the op-amp will maintain stability in Vi with a reference point to give the current IB to the transistor Q1. So at all times maintain the stability of the Op-amp:

Vin (-) = ½

By ignoring the VBE voltage of transistor Q1 and mensubsitusi formula (11) into the formula (10) of the obtained mathematical relationship:

Vout = ((R1 + R2) / R2) ½

In this circuit the output voltage can be set by adjusting R1 and R2 large.

Now it should no longer need to painstakingly search for the op-amp, transistors and other components to realize the regulator circuit as above. Because this kind of circuit has been packaged into a single fixed voltage regulator IC. Are now widely known as the 78XX series components of the voltage regulator to remain positive and 79XX series which is a voltage regulator to remain negative. In fact, these components are usually already equipped with current limiting (current limiter) and also limiting the temperature (thermal shutdown). This component is only three pins and by adding some components alone can be a series of power supply regulation was good.

semiconductor diode

2011-09-18T20:31:00.006-07:00

Physical function
An LED is a special type of semiconductor diode.
Like a normal diode, an LED consists of a chip of semiconducting material is fully charged, or in-bulb, with impurities to create a structure called a pn junction.
-Charge carriers - electrons and holes flow into the junction from electrodes with different voltage.
When an electron meets a hole, he fell into a lower energy level, and release energy in the form of photons.

Light emission
The wavelength of light emitted, and therefore its color, depending on the difference in the energy band of the material that forms a pn junction.
A normal diode, typically made of silicon or germanium, emits visible light near infrared, but the material used for an LED have a difference between the energy band near infrared light, visible, and near ultraviolet.

Substrate LED
LED development began with infrared and red devices made with gallium arsenide.
Perkembagan in materials science have enabled the production of tools with shorter wavelengths, producing light with varied colors.

Conventional LEDs are made from inorganic mineral that varies, resulting in the following colors:
* Aluminum gallium arsenide (AlGaAs) - red and infrared
* Gallium aluminum phosphide - green
* Gallium arsenide / phosphide (GaAsP) - red, orange-red, orange, and yellow
* Gallium nitride (GaN) - green, pure green (or emerald green), and blue
* Gallium phosphide (GaP) - red, yellow, and green
* Zinc selenide (ZnSe) - blue
* Indium gallium nitride (InGaN) - turquoise and blue
Aluminum gallium indium phosphide * - orange-red, orange, yellow, and green
* Silicon carbide (SiC) - blue
* Diamond (C) - ultraviolet
* Silicon (Si) - blue (under development)
* Sapphire (Al2O3) - blue

Positive voltage phase of the first forwarded by D1, while the next phase which is passed through D2 to the load R1 with transformer CT as a common ground .. Thus the load R1 gets a full wave voltage supply like the picture above. For some applications such as for supply to a small dc motor or dc incandescent lamps, the shape of this voltage is sufficient. Although the voltage ripple seen here from the second series of the above is still very large.
series of half-wave rectifier with filter capacitor C is parallel to the load R. Apparently with this filter out the voltage waveform can be flat. Figure-4 shows a DC voltage output from circuit half-wave rectifier with capacitor filter. Bc line is approximately straight line with a certain slope, which in this state for the load current supplied by voltage capacitor R1. Actually the line bc is not a straight line but exponential in accordance with the nature of discharging the capacitor.
Bc depends on the slope of the curve of current (I) which flows to the load R. If the current I = 0 (no load) then the curve will form a horizontal line bc. But if the load currents greater, the slope of the curve bc will be more sharp. The voltage that comes out will be shaped with a sawtooth ripple voltage of magnitude are:

VR = VM-VL

and dc voltage to the load is Vdc = VM + Vr / 2

A good rectifier circuit is a circuit that has a ripple voltage (Vr) the smallest. VL is the voltage discharge or discharge the capacitor C, so it can be written:

VL = VM e -T/RC

If equation (3) disubsitusi to formula (1), then diperole

VR = VM (1 - e -T/RC)

If T <

For example, you design a full wave rectifier circuit of the power supply 220V/50Hz grid to supply the load of 0.5 A. What is the value capacitors are necessary so that this circuit has a voltage ripple of not more than 0.75 Vpp. If the formula (7) turned upside down then obtained.

C = I.T / Vr = (0.5) (0.01) / 0.75 = 6600 UF

For capacitors that are widely available for elco type that has a maximum working voltage polarity and specific. Working voltage capacitors used must be greater than the power supply output voltage. You may now understand why you created a series of audio buzzing, trying to check the power supply rectifier circuit that you created, if the voltage ripple is quite disturbing. If the market is not available such a large capacitor, it could with two or three pieces paralel capacitor.

Light emission

2011-09-18T20:31:00.005-07:00

SCR stands for Silicon Control Rectifier

2011-09-18T20:31:00.004-07:00

SCR stands for Silicon Control Rectifier.

SCR Silicon Control acronym stands for Silicon Control Rectifier.SCR Rectifier.SCR acronym stands for Silicon Control Rectifier.SCR Silicon Control Rectifier.

To SCR:
* As a series of switches (switch control)
* As a series controller (remote control)
There are three major groups for these semiconductors are equally able to function as a switch (switching) at a voltage 120 volts to 240 volts.
The third group is itself SCR, DIAC and TRIAC.

DIAC is one type of diode SCR, but it has two terminals (electrodes) alone, in contrast with the "brother" who has three terminals, TRIAC.

DIAC on electronic schematic symbols

In the diagram shows there are five layers in the DIA, has two terminals of the terminal 1 (T1) and terminal 2 (T2).

TRIAC
TRIAC has a construction similar to DIAC, TRIAC contained only the control terminal (gate terminal).
As for the other terminal is called a main terminal and main terminal 2 (abbreviated MT1 and MT2).
As with the DIAC, TRIAC can flow through the alternating current, unlike SCR drain only direct current (from anode to cathode terminal terminal).

TRIAC symbol in the scheme of electronics, has three legs, two of which MT1 terminal (T1) and MT2 (T2) and the other terminal Gate (G)

The triac is equivalent to two parallel connected SCR.
This means that the switch TRIAC can be both directly.
TRIAC classified according to the ability of contacting. TRIAC does not have a very high power capability for this type of SCR.

There are two types of TRIAC, Low-Current and Medium-Current.
Low-Current TRIAC may contact up to a strong current of 1 ampere and has a maximum voltage of up to several hundred volts.
Medium-Current TRIAC can be contacted through strong currents have a maximum of 40 amperes and voltages up to 1,000 volts.

A Zener diode

2011-09-18T20:31:00.003-07:00

A diode is usually regarded as the tool that supply power to one direction, but the Zener diodes are such that current can flow in the opposite direction if the applied voltage overshoot "voltage is broken" (breakdown voltage) or "Zener voltage".

Usual diode will not allow electric current to flow in the opposite if the reverse-biased (reverse-biased) below the breakdown voltage.
If the breakdown voltage exceeds the limit, regular diodes will be damaged because of excess electrical current that causes heat.
However, this process is reversible if done within limits.

In the case of rationing-forward (in the direction of the arrow), this diode will provide a voltage drop (voltage drop) of about 0.6 volts for a normal silicon diode.
The voltage drop depends on the type of diode used.

A Zener diode has properties similar to ordinary diode, except that the tool is deliberately made with a much reduced tengangan damaged, called Zener voltage.

A Zener diode has a pn junction which has a heavy doping, which allows electrons to penetrate (tunnel) from the valence band p-type material into the conduction band n-type material.

A zener diode is reverse-biased will exhibit a controlled breakdown and will pass an electric current to keep the voltage drop in order to remain on the zener voltage.

For example, a 3.2 Volt zener diode will show a voltage drop at 3.2 Volts if given the supply and forth.
However, because the current is not unlimited, so the zener diode is typically used to generate a reference voltage, or to stabilize the voltage for small flow applications.

Breakdown voltage can be controlled accurately in the doping process.
Tolerance of 0.05% could be achieved although the most usual tolerance is 5% and 10%.
This effect was discovered by an American physicist Clarence Melvin Zener.

Other mechanisms that produce the same effect is the avalanche effect, as in avalanche photodiodes.
Both types of diodes are actually formed through the same process and the effects actually occur in both types of these diodes.
In silicon diodes up to 5.6 volts, the zener effect is the main effect and this effect showed a negative temperature coefficient.
Above 5.6 volts, the avalanche effect becomes the main effect and also showed a positive temperature coefficient characteristics.

In the 5.6 volt zener diode, both effects occur together, and second temperature coefficients cancel each other.
Thus, diodes 5.6 volt the top choice in the temperature-sensitive applications.
The techniques of modern manufacturing has made it possible to create diodes which have a much lower voltage of 5.6 volts with a very small temperature coefficient.
But with the advent of high-voltage users, the temperature coefficient also appears with the speedy way. A diode for 75 Volt has a coefficient that is 10 times as much heat coefficient of a diode 12 Volt.

All the diodes on top, no matter whatever tengangan damage, usually sold called Zener diodes.

Usage

Zener diodes are usually used extensively in electronic circuits.
Its main function is to stabilize the voltage.
At the time are connected in parallel with a source voltage swings are mounted so that the dole and forth, a zener diode will act like a short circuit (short circuit) when the voltage reaches the diode voltage was faulty.
The result, the voltage will be limited up to a figure that has been known previously.

A zener diode is also used like this as a shunt voltage regulator (shunt connection is parallel, and voltage regulator circuit as a class that provides a fixed voltage source.

Laser diode

2011-09-18T20:31:00.002-07:00

Laser diode is a type of laser in which the active medium of a semiconductor pn junction similar to that found on light-emitting diodes.
Diode lasers are also sometimes abbreviated as LD or ILD.

The new laser diode is found at the end of this century by scientists at Harvard University. The working principle of this diode is the same as any other diode through the circuit of the electronic circuit, which consists of type p and n. In both types is often produced two voltages, namely:
1. forward biased, current is generated in line with the value of 0.707 for the distribution of V peak, the wave form above (+).
2. backforward biased, this is turning the voltage that can damage an electronic component.

Photo diode

2011-09-18T20:31:00.001-07:00

Photo diode is a type of diode which functions to detect light.
In contrast with ordinary diodes, electronic components will transform light into electrical current.
Light that can be detected by the photo diode is ranging from infrared light, visible light, ultra-violet to X-rays.
Photo diode applications ranging from vehicles on public roads counter automatically, the camera's light meter and some equipment in the medical field.

Tool similar to the photo diode is a photo transistor (Phototransistor).
This photo transistor is basically a type of bipolar transistor using the contact (junction) base-collector to receive light.

This component has a better sensitivity when compared with Photo Diode.
This is caused by electrons generated by photons of light at this junction is injected at the base and reinforced at the collector.
However, the response time of the photo-transistors in general will be slower than on-Photo Diode.

Blue LED

2011-09-18T20:31:00.000-07:00

The first blue LEDs that can achieve commercial information using gallium nitride substrates which was invented by Shuji Nakamura in 1993 during a career at Nichia Corporation in Japan.
LED was then popular in the late 90's.

Blue LED can be combined into the red and green LEDs that have been there before to create white light.

With white LED light is now the majority are made by coating a substrate of gallium nitride (GaN) with yellow phosphorus.
Because the color yellow stimulates the red and green color receivers in the human eye, the combination of yellow and blue phosphors of the substrate will give the impression of a white color for the human eye.

White LEDs can also be made by coating the phosphor blue, red and green in the substrate near ultraviolet is more or less similar to the way fluorescent lamps work.

Current methods for creating white light from LEDs is to not use phosphorus at all but uses a zinc selenide substrate which can emit blue light from the active area and the yellow light from the substrate itself.

signal crossing

2011-09-16T19:56:00.000-07:00

compressor to react fast or slowly to an audio signal crossing the Threshold and also how long the compressor keeps working. A loud acoustic guitar being plucked is a good example. With a fast Attack time the musicians playing will be compressed almost instantly. What if you want to hear that definite click of the plectrum plucking the strings? You set a slower Attack time which allows that plucking noise through before the compressor cuts in to reduce the overall volume. Its like shutting the digital barn door after the horse has bolted. Okay, now you want the compressor to turn itself off again in time to hear the next plectrum pluck. So you want a fast Release time to get that compressor out of the way. Otherwise with a slow Release time the compressor will still be on and effecting the following picking.

Different situations call for other approaches. A fast Attack time will help remove plosives, such as microphone popping. If you get your Attack and Release settings wrong it can create a pumping effect as the compressor struggles against the signal.

GPS front end RF

2011-09-15T06:59:00.000-07:00

Built-in GPS front end RF and base band processing module
GPS Antenna Provided
Local Alphanumeric or Graphics display to display Latitude/Longitude/Altitude and Direction
The above parameters can be transmitted through a RS232 output port
This RS232 output is fed to a local wireless transmitter at 433.0 MHz frequency
The range of coverage is 8-10Kms can be expandable to 15Km.
FSK modulation.
Yagi antenna with 8-10dBm Gain for Transmission.
Log scale fidelity : ±2 dB (without attn.) 500 MHz
input attenuator : 0 to 40 dB (4X10 dB steps)
Max.input level :+10 dBm, ±25V DC(odB attn.) +20 dBm (40 dB attn.)
Tracking generator
Output frequency : 0.15 MHz to 1050 MHz
Output attenuator : 0 to 40 dB (4X10 dB steps)
Output impedance : 50 (BNC)
Output level range : -50 dBm to + 1dBm (in 10 dB steps and var)

digital communication

2011-09-15T06:25:00.000-07:00

We have in store for our clients a quality range of communication trainers, digital communication trainer and analog comminucation trainer etc that has gained appreciation for easy usage and optimum utility. Our range includes analog communication trainers, antenna trainers, mobile trainers and transmission line trainers. These trainers are ideal for conducting varied experiments in the field of telecommunications, electronics and electrical labs.

EPABX TRAINER

2011-09-15T05:58:00.000-07:00

EPABX TRAINER
We are amongst the renowned manufacturers and exporters of trainer kits that are available in various models. Our range comprises instrumentation trainers kits, consumer electronic trainers and bio medical trainers. These find application in telecommunication industry, public utilities and medical sector.

We are engaged in offering quality range of instrumentation trainers kit that has gained appreciation for reliable operations. These include ITK-01 LVDT trainer kit, ITK-02 pressure measurement kit, ITK-10 angular displacement kit and ITK 11 thermistor, AD 590 kit.

We offer Basic Science/ Physics Trainers that are generally used in the experiments of science and physics in educational institutes and universities. It is checked on various parameters such as performance, accuracy in readings and durability. The trainers find application in government agencies, academic institutions and research centers.

Digital Interface

2011-09-15T05:42:00.000-07:00

XGGCOMMS Icom Digital Interface
Description: This interface offers full CAT control of your Icom Transceiver via your PC's RS-232 port and the Radio's 3.5mm CAT (CI-V) Jack . Additionally, the interface connects your PC sound card line in/out jacks to the radio's 8 pin Din accessory socket for full transmit and receive audio interfacing allowing you to operate modes such as PSK-31, WEFAX, SSTV, PACTOR, Packet, AFSK CW and many more.

This interface is compatible with:
IC-275, IC-375, IC-575, IC-707, IC-725, IC-726, IC-728,
IC-729, IC-735, IC-736, IC-737, IC-738, IC-746,
IC-746Pro, IC-756, IC-756Pro2, IC-756Pro3, IC-761,
IC-765, IC-775, IC-775DSP, IC-7400, IC-7700, IC-7800,
IC-781, IC-820, IC-821, IC-910, IC-970.

CPLD

2011-09-15T04:23:00.001-07:00

Modular design and flexibly for CPLD
Signal generation unit:
Programmable frequency generator
Standard frequency: 1 — 10MHz
Logic input switch:
8 x 1 logic input original press point with light
8 x 2 logic input Dip switch
4 impulse press button generator
3 x 4 array keyboard
Output unit:
Logic status monitor with total 102 sets LED indicator
8 x 8 dual color point array LCD display
LCD 16 x 2 monitor
6 digits 7 nodes monitor
3 x 4 LED and 1 set buzzer output
Linear unit:
2 sets 8bit D/A converter
1 set 8bit A/D converter
MPU unit:
08051 and CPLD match circuit test
Power source: 220-240V AC, 50Hz, 1Phase
Standard accessories with printed operation manual

voltage-controlled oscillator

2011-08-25T05:32:00.000-07:00

VCO also has a connection for an external induction coil for use in showing how magnetically induced voltages can vary the audio frequency output. The audio output of the VCO can also be varied between 500 Hz and 5 KHz by means of a potentiometer. To view schematics of the VCO in Adobe Acrobat format click on the links below.

The VCO is powered off of two nine volt batteries connected in series. Circuit common is tapped off of the junction between the two batteries which results in +9VDC and +9VDC supplies for the VCO. The power supplies are regulated to +5VDC and -5VDC supplies that are used by the MAX038 chip. The unregulated +9VDC supply is used by LM386 audio amplifier and LM555 timer chip. The W172DIP-141 reed relay chip also uses the +5VDC supply for its coil voltage.

voltage-controlled oscillator (VCO) is a frequency-varying oscillation circuit that changes its output frequency according to an external voltage. The varying range of the frequency is determined according to its purposes. A typical voltage controlled oscillator (VCO) generates an output signal oscillating at a frequency determined in accordance with a voltage supplied from an external unit. A VCO employs one or more variable capacitors (varactors) to allow for adjustment of the frequency of oscillation for the VCO. Voltage controlled oscillators mainly produce high frequency signals. The frequency of these high frequency signals generally depends upon the capacitive value of a resonant circuit.

PIN AND FUNCTION DATA ON TELEVISION 2010 Flyback

2011-08-24T23:10:00.000-07:00

PIN AND FUNCTION DATA ON TELEVISION 2010 Flyback

** TV SHARP

F 0102KM-SA
F 093PEN1-SA
JF 0501-3261
BSC 26-263
C/B+/Gnd/24v/16v/Afc/180v/Gnd/Heater/Abl
=========================
*pada TV GOLDSTAR

154-064P
15g-177B
FCK-14B047
C/180v/B+/Gnd/16v/24v/Abl/Heater/A
=========================
K 148 TC
C/180v/B+/Gnd/Afc/16v/Abl/Heater/Nc/Nc
=========================
FCG 2045 BL
Afc/16,5v/Heater/Boost-up/B+/83v/Gnd/Nc/C/Abl/175v/24v
=========================
DCF 2217J
C/B+/Bosot-up/16,5v/24v/Abl/Gnd/200v/Heater/
=========================
FSA 16012M
DCF 2077A
DCF 1577
C/B+/Afc/Boos-up/16,5u/Abl/+-a5v/Gnd/185v/Heater
=========================
* TV SANSUI

JF 0601-19577
C/B+/180V/16V/25V/Heater/Gnd/Abl/Afc/Nc
=========================
*pada TV Politron

JF 0601-19577
C/B+/Gnd/200v/Nc/Heater/Nc/Abl/+12v/-12v
=========================
* TV Digitec/Politron

FCK 14A006
FCM 2015HE
FCM 14A032
C/B+/Abl/24v/Heater/16v/180v/Gnd/Nc/Abl
=========================
* TV Politron

FCM 20B061N
C/B+/Gnd/185v/Nc/Heater/Nc/Abl/+12v/-12
=========================
* TV Akari

FUY-20C009
C/180V/B+/Gnd/Nc/24v/Nc/Abl/Heater/Afc
=========================
* TV Changhong

BSC 65A
C/B+/190v/Gnd/Nc/Nc/14,5v/Abl/Heater/Afc
=========================
* pada TV Intel

154-132A
154-123c
C/40v/16,5v/Heater/Gnd/B+/180v/Gnd/Abl/40v
=========================
FCK 14111 L01
FCM 14A025
C/Boost-up/Abl/B+/Gnd/180v/24v/Heater/Afc/16,5v
=========================
154 189H
154 2777C
FCM 20B027
C/B+/180v/ 16v/24v/Heater/Gnd/Abl/Afc/Nc
=========================
MC-FBC-015
LCE CF0854
C/B+/Gnd/Afc/185v/Heater/25v/15v/Gnd/Abl
=========================
* TV Samsung

FSV-20A001
FCK-14A033
FSV-14A001
C/B+/125v/Abl/Nc/Gnd/185v/46v/Heater/Nc/16,5v
=========================
* TV SamsunG

FTK-14A00P
C/B+/125v/Abl/Nc/Gnd/180v/24v/Heater/Afc/16,5v
=========================
* TV Sony kv-PG-21P70

8-598-858-00
8-598-811
C/B+/135v/200v/Heater/Gnd/-16v(vertikal/Gnd (verikal/+16,5/vertikal/Nc/Abl
=========================
*pada TV Sony KV-G21P1

8-598-960-00
C/B+/115V/200v/Heater/Gnd/-13v/Gnd/+15v/Nc/Abl
=========================
* TV Thosiba

TFB 4125 DY
TFB 4125 HY
C/B+/180v/Gnd/Nc/25v/12v/Abl/Heater/Afc
=========================
BSC 22-01-06
BSC 25-48
BSC 25-4803
BSC 24-01N362
C/B+/Nc/Afc//Gnd/Heter/Abl/Nc
=========================
* TV Cina

BSC 24-01N4014K
BSC 25-T1010A
BSC 25-09N21A
BSC 25-05N2110A
BSC 25-09N20E
C/Tep/B+/Tep/Tep/Gnd/Heater/Abl/180v
=========================
* TV Konka K21697C

BSC 25-2678S
C/200v/B+/Gnd/Afc/16v/Abl/Heater/Nc/Nc
=========================
* TV CINA 29

JY0301-0206
C/B+/Nc/Afc/Gnd/Heater/Abl/Tep/Tep/Tep/Tep
=========================
* TV Goldstar

154-064P
154-177B
FCK-14B047
C _ 180v _ B+ _ Gnd _ 16v _ 24v _ 40v _ Abl _ Heater _ Afc
==========================
F 0101KM-SA
F 0141 PE-M
C _ B+ _ Gnd _ 24v _ 16v _ Afc _ 180v _ Gnd _ Heater _ Abl
==========================
K 148 TC
C - 180v _ B+ - Gnd _ Afc _ 16v _ Abl _ Heater _ Nc _ Nc
==========================
FCG 2045 BL
Afc - 16,5v _ Heater _ Boost-up _ B+83v _ Gnd _ Nc _ C _ Abl _ 175v _ 24v
==========================
FSA 16012M
DCF 2077A
DCF 1577
FSA 16012M
C - B+ - Afc _ Boost-up _ 16,5 _ Abl _ 25v _ Gnd _ 185v _Heater
==========================
* TV sansui

JF 0501-1206
C _ B+ _ 180v _ 16v _ 25v _ Heater _ Gnd _ Abl _ Afc _ Nc
==========================
* TV politron

JF0601-19577
C_B+_gnd_200v_nc_Ht_nc_abl_+12_-12
==========================
* TV digitec, polytron

FCK 14A006
FCM 2015HE
FCM 14A032
C _ B+ _ Abl _ 24v _ Heater _ 16v _ 180v _ Gnd _ Nc _ Abl
==========================
* TV politron

FCM-20B061N
c_B+_gnd_185_nc_Ht_Nc_abl_+12_-12
===========================
* TV AKARI

FUY-20C009
C_180_B+_gnd_nc_24_nc_abl_Ht_afc
===========================
* TV changhong

BSC 65A
C _ B+ _ 190v _ Gnd _ Nc _ Nc _ 14,5v _ Abl _ Heater _ Afc
===========================
* tv intel

154 - 132A
154 - 132C
C _ 40v _ 16,5 _ Heater _ Gnd _ B+ _ 180v _ Gnd _ Abl _40v
===========================
FCK 1411 L 01
FCM 14A025
C _ Boost-up _ Abl _ B+ _ Gnd _ 180v _ 24V _ Heater _ Afc _ 16,5v
===========================
154 189H
154 277C
FCM 20B027
C _ B+ _ 180v _ 16v _ 24v _ Heater _ Gnd _ Abl _ Afc _ Nc
===========================
MC - FBC-015
LCE CF0854
C _ B+ _ Gnd _ Afc _ 185 _ Heater _ 25 _ 15 _ Gnd _ Abl
===========================
* TV samsung

FSV - 20A001
FCK - 14A033
FSV - 14A001
C _ B+125v _ Abl _ Nc _ Gnd _ 185 _ 46 _ Heater _ Nc _ 16,5
===========================
* TV samsung

FTK-14A004P
C_B+125v_ABL_ Nc_ Gnd_ 180v_24v_Ht_afc_16,5
===========================
* TV toshiba

TFB 4125 DY
TFB 4125 HY
C _ B+ _ 180 _ Gnd _ Nc _ 26v _ 12v _ Abl _ Heater _ Afc
===========================
BSC 22-01-06
BSC 25-48
BSC 25-4803
BSC 24-01N362
C _ B+ _ Nc _ afc _ gnd _ Heater _abl _ nc
===========================
BSC25-2678S konka K2169TC
C_200v_B+_ gnd_afc_16v_abl_ht_nc_nc
===========================
JY0301-0206 tv china 29
C_B+_nc_afc_gnd_HT_abl_tep_tep_tep
===========================
DCF 2217J
C _ B+ _ afc _ boost-up _ 16,5 _ 24 _ abl _ gnd _ 200v _ heater
===========================

F0101 KM-SA sharp 14R20
F0102 KM-SA sharp 20R20B, 20R200, 51R200
C_B+_GND_24V_16V_AFC_180V_GND_HT_ABL
===========================
FA122WJ-B
C_B+(130V)_GND_24V_NC_AFC_180V_GND_HT_ABL
===========================
F094
FA061 WJ-SA sharp 51X200
C_B+(130V)_GND_24V_12V_AFC_185V_GND_HT_ABL
===========================
F0122 PE-M sharp 20Q250
C_B+_24V_16V_NC_AFC_GND_HT_180V_ABL
===========================
F0147
C_B+_GND_24V_16V_AFC_180V_GND_HT_ABL
===========================
F0194 PEN1-SA sharp 20R200MKII, 51U200, 20W200
F2037 PE-B sharp 20AG2-S
C_B+_GND_40V_16V_AFC_180V_GND_HT_ABL
===========================
FA011 WJ-B sharp
C_B+_GND_24V_16V_AFC_180V_NC_HT_ABL
===========================
FA060 WJ-SA sharp 14S20MKII
C_B+_CND_NC_12V_AFC(-12V)_180V_GND_HT_ABL
===========================
FA113 WJ-B sharp 51DXF250E
C_B+_GND_24V_NC_AFC_180V_GND_HT_ABL
===========================
F0193 PEN1-SA sharp 14U15
C_B+(115)_GND_40V_12V_AFC_180V_GND_HT_ABL
===========================
F0101 KM-SA sharp 14R20
F0102 KM-SA sharp 20R20B, 20R200, 51R200
C_B+_GND_24V_16V_AFC_180V_GND_HT_ABL
===========================
FA122WJ-B
C_B+(130V)_GND_24V_NC_AFC_180V_GND_HT_ABL
===========================
F094
FA061 WJ-SA sharp 51X200
C_B+(130V)_GND_24V_12V_AFC_185V_GND_HT_ABL
===========================
F0122 PE-M sharp 20Q250
C_B+_24V_16V_NC_AFC_GND_HT_180V_ABL
===========================
F0147
C_B+_GND_24V_16V_AFC_180V_GND_HT_ABL
===========================
F0194 PEN1-SA sharp 20R200MKII, 51U200, 20W200
F2037 PE-B sharp 20AG2-S
C_B+_GND_40V_16V_AFC_180V_GND_HT_ABL
===========================
FA011 WJ-B sharp
C_B+_GND_24V_16V_AFC_180V_NC_HT_ABL
===========================
FA060 WJ-SA sharp 14S20MKII
C_B+_CND_NC_12V_AFC(-12V)_180V_GND_HT_ABL
===========================
FA113 WJ-B sharp 51DXF250E
C_B+_GND_24V_NC_AFC_180V_GND_HT_ABL
===========================
F0193 PEN1-SA sharp 14U15
C_B+(115)_GND_40V_12V_AFC_180V_GND_HT_ABL
===========================
154-064P Goldstar
154-177B
FCK-14B047
C _ 180v _ B+ _ Gnd _ 16v _ 24v _ 40v _ Abl _ Heater _ Afc
===========================
F 0101KM-SA
F 0141 PE-M
C _ B+ _ Gnd _ 24v _ 16v _ Afc _ 180v _ Gnd _ Heater _ Abl
===========================
K 148 TC
C - 180v _ B+ - Gnd _ Afc _ 16v _ Abl _ Heater _ Nc _ Nc
===========================
FCG 2045 BL
Afc - 16,5v _ Heater _ Boost-up _ B+83v _ Gnd _ Nc _ C _ Abl _ 175v _ 24v
===========================
FSA 16012M
DCF 2077A
DCF 1577
FSA 16012M
C - B+ - Afc _ Boost-up _ 16,5 _ Abl _ 25v _ Gnd _ 185v _Heater
===========================
JF 0501-1206 sansui
C _ B+ _ 180v _ 16v _ 25v _ Heater _ Gnd _ Abl _ Afc _ Nc
===========================
JF0601-19577 (polytron)
C_B+_gnd_200v_nc_Ht_nc_abl_+12_-12
===========================
FCK 14A006 digitec, polytron
FCM 2015HE
FCM 14A032
C _ B+ _ Abl _ 24v _ Heater _ 16v _ 180v _ Gnd _ Nc _ Abl
===========================
FCM-20B061N (polytron)
c_B+_gnd_185_nc_Ht_Nc_abl_+12_-12
===========================
FUY-20C009 (akari)
C_180_B+_gnd_nc_24_nc_abl_Ht_afc
===========================
BSC 65A changhong
C _ B+ _ 190v _ Gnd _ Nc _ Nc _ 14,5v _ Abl _ Heater _ Afc
===========================
154 - 132A intel
154 - 132C
C _ 40v _ 16,5 _ Heater _ Gnd _ B+ _ 180v _ Gnd _ Abl _40v
===========================
FCK 1411 L 01
FCM 14A025
C _ Boost-up _ Abl _ B+ _ Gnd _ 180v _ 24V _ Heater _ Afc _ 16,5v
===========================
154 189H
154 277C
FCM 20B027
C _ B+ _ 180v _ 16v _ 24v _ Heater _ Gnd _ Abl _ Afc _ Nc
===========================
MC - FBC-015
LCE CF0854
C _ B+ _ Gnd _ Afc _ 185 _ Heater _ 25 _ 15 _ Gnd _ Abl
===========================
FSV - 20A001 samsung
FCK - 14A033
FSV - 14A001
C _ B+125v _ Abl _ Nc _ Gnd _ 185 _ 46 _ Heater _ Nc _ 16,5
===========================
FTK-14A004P (samsung)
C_B+125v_ABL_ Nc_ Gnd_ 180v_24v_Ht_afc_16,5
===========================
8-598-858--00 sony KV-PG21P70
8-598-811
C _ B+135v _ 200v _ Heater _ Gnd _ -16,5(vertkl) _ Gnd(vertkl) _ +16,5(vertkl) _ Nc _ Abl
===========================
8-598-960-00 sony KV-G21P1
C_b+115V_200V_ht_ gnd_-13v_gnd_+15v_nc_abl
===========================
TFB 4125 DY (thosiba)
TFB 4125 HY
C _ B+ _ 180 _ Gnd _ Nc _ 26v _ 12v _ Abl _ Heater _ Afc
===========================
BSC 22-01-06
BSC 25-48
BSC 25-4803
BSC 24-01N362
C _ B+ _ Nc _ afc _ gnd _ Heater _abl _ nc
===========================
BSC 24-01N4014K tv china
BSC 25-T1010A
BSC 25-09N21A
BSC 25-05N2110A
BSC 25-09N20E
Tep _ C _ Tep _ B+ _ Tep _ Tep _ gnd _ Heater _ abl _ 180v
===========================
BSC25-2678S konka K2169TC
C_200v_B+_ gnd_afc_16v_abl_ht_nc_nc
===========================
JY0301-0206 tv china 29
C_B+_nc_afc_gnd_HT_abl_tep_tep_tep
===========================
DCF 2217J
C _ B+ _ afc _ boost-up _ 16,5 _ 24 _ abl _ gnd _ 200v _ heater
===========================

ARM926EJ-S

2011-08-22T21:29:00.000-07:00

The ARM Subsystem integrates the ARM926EJ-S processor. The ARM926EJ-S processor is a member of
ARM9 family of general-purpose microprocessors. This processor is targeted at multi-tasking applications
where full memory management, high performance, low die size, and low power are all important. The
ARM926EJ-S processor supports the 32-bit ARM and 16 bit THUMB instruction sets, enabling the user to
trade off between high performance and high code density. Specifically, the ARM926EJ-S processor
supports the ARMv5TEJ instruction set, which includes features for efficient execution of Java byte codes,
providing Java performance similar to Just in Time (JIT) Java interpreter, but without associated code
overhead.
The ARM926EJ-S processor supports the ARM debug architecture and includes logic to assist in both
hardware and software debug. The ARM926EJ-S processor has a Harvard architecture and provides a
complete high performance subsystem, including:
• ARM926EJ -S integer core
• CP15 system control coprocessor
• Memory Management Unit (MMU)
• Separate instruction and data Caches
• Write buffer
• Separate instruction and data Tightly-Coupled Memories (TCMs) [internal RAM] interfaces
• Separate instruction and data AHB bus interfaces
• Embedded Trace Module and Embedded Trace Buffer (ETM/ETB)

digital-display capacitor

2011-08-22T21:21:00.000-07:00

The digital-display capacitor is an energy storage device, it is designed to supplement the audio amplifiers power supply during high current demand. An example of such a demand is when music hits a low bass transient. The overall bass response of an audio system will be enhanced by using this device. It is capable of storing a large amount of energy which can be discharged very fast when needed. This makes the power cap a logical addition to the audio system as automotive batteries are not designed to deliver the current required in high power car audio installations. Another feature of the digital display capacitor is its availability to filter car AC voltage induced by the amplifier's power supply. This can otherwise cause audible noise in the sound system of the car.

– Digital Power Stabilizing Capacitor
– Internally Stacked Capacitors (foil-carbon)
– Electronics Polarity Protection Circuit
– Satin finish with chrome end caps and mounting brackets
– Aluminum case gift box with front glass window

EEPROM

2011-08-22T20:13:00.000-07:00

Electrically erasable programmable read-only memory (EEPROM) chips are similar to PROM devices, but require only electricity to be erased. Architecture or status, performance, power characteristics, and packaging information are all important parameters to consider when searching for EEPROM memory chips.

Electrically Erasable Programmable ROM) A rewritable memory chip that holds its content without power. EEPROMs are bit or byte addressable at the write level, which means either the bit or byte must be erased before it can be re-written. In flash memory, which evolved from EEPROMs and is almost identical in architecture, an entire block of bytes must be erased before writing. In addition, EEPROMs are typically used on circuit boards to store small amounts of instructions and data, whereas flash memory modules hold gigabytes of data for digital camera storage and hard disk replacements

Intersil X90100 is a non-volatile electronically programmable capacitor. The device is programmed through a simple digital interface. After programming, the chosen setting for the device is retained by internal EEPROM storage whether or not DC power is maintained. There are 32 programmable capacitance values selectable, ranging from 7.5pF to 14.5pF in 0.23pF increments, in single-ended mode. The dielectric is highly stable, and the capacitance
exhibits a very low voltage coefficient. It has virtually no dielectric absorbtion and has a very low temperature drift coefficient in differential mode (<50ppm/°C). The X90100 is programmed through three digital interface pins, which have Schmitt triggers and pullup resistors to secure code retention. The three pins, INC, U/D, and CS, are identical in operation to other Intersil chips with up/down interface, such as the X9315 5-bit Digitally Controlled Potentiometer (DCP).

EEPROM and flash memory bit cells are CMOS-based transistors that hold a charge on a "floating gate." With no charge on the floating gate, the transistor acts normally, and a pulse on the control gate causes current to flow. When charged, it blocks the control gate action, and current does not flow. Charging is accomplished by grounding the source and drain terminals and placing sufficient voltage on the control gate tunnel through the oxide to the floating gate. A reverse voltage channeled from another transistor clears the charge by causing it to dissipate into the substrate.

Electrolytic conductor

2011-08-22T06:35:00.000-07:00

In chemistry, the electrolyte is a substance containing free ions that make it electrically conductive. The most common type of electrolyte is a solution of ions, but the fused substance electrolytes and solid electrolytes are also there.

Electrolyte is a substance that dissolves or decomposes into the form of ions and the subsequent solution of the electrical conductor, the ions are electrically charged atoms. Electrolyte can be water, acid, base or other form of chemical compounds. Electrolytes are generally in the form of acid, alkali or salt. Some of the specific gas can serve as an electrolyte in certain conditions such as high temperature or low pressure. Strong electrolyte is identical with acids, bases, salts and strong. Electrolytes are compounds that bind to ionic and polar covalent. Most of the compounds that bind ion as an example of an electrolyte NaCl ionic bond, which is one type of salt that is salt. NaCl preformance can be electrolyte solution and form a melt. or liquid form and aqueous. whereas in the form of solid or solid ionic compounds can not serve as an electrolyte.

Electrolytes generally exist in the form of acidic, alkaline, or salt. Several types of gas can also serve as an electrolyte in high temperature conditions and low pressure (eg when there is lightning and the workings of a plasma TV). Electrolyte solution can also be produced from a solution of biological compounds (DNA and polypeptides, genes used in the separation process) and synthetic polymers (called polyelectrolytes; eg polystyrene sulfonate).

Electrolyte solution is generally formed when salts are dissolved in a solvent such as water, and salt components separate due to thermodynamic interactions between solvent and solute, a process called solvation. For example, the salt is dissolved into water. Salt as a solid form would be dissolved into its constituent components, namely Na + and Cl-.

Electrolytes can also be made by dissolving the substance in which these substances also react with water, for example, dissolving carbon dioxide gas into water to produce a solution containing H + ions, carbonate, and carbonic acid (eg, in the process of making carbonated beverages).

Molten substances that are usually dissolved in a solvent for the electrolyte solution can also be an electrolyte as well, such as molten salt that can conduct electricity.

Strength of the electrolyte depends on the amount of ions dissolved in it. If the substance is dissolved does not produce ions, then it is said to be non-electrolytes. Or if the resulting ions are few in number because of the ability dissosiatifnya with a weak solvent, then it is said a weak electrolyte solution, and only able to conduct electricity in very limited quantities.

Adalam strong solution of electrolyte solution that has good electrical conductivity, because the substance inside terarut entirely solvent can be transformed into ions. Classified as strong electrolytes are: strong acids (HCl, HClO3, HClO4, H2SO4, HNO3, etc.), strong bases (bases of alkali and alkaline earth group), and salts with high solubility (NaCl, KCl, KI, Al2 (SO4) 3, and so on).

Weak electrolyte solution is a solution that can conduct electrical currents are weak because of the solute components are not entirely transformed into ions, but only partially. Classified as a weak electrolyte solution is a weak acid, weak base, and salt-soluble salts (AgCl, CaCrO4, PbI2, and so on).

Non electrolyte solution is a solution of the components of the solute can not be turned into ions. This is because the molecular bond is too strong so it is difficult to separate themselves in the solution. Generally, a solution of polymer compounds and polymer compound itself is a non electrolyte. An example is the urea solution, sucrose solution, glucose solution, alcohol solution, and so on.

When electrodes are placed in the electrolyte and the electrical voltage applied, the electrolyte will conduct electricity. Chemical reactions will occur at the cathode consuming electrons released by the anode, and other reactions occur at the anode that emit electrons to the cathode was arrested. This will produce a cloud of electrons surrounding the cathode and electron-poor conditions at the anode. To overcome this, the ions in the solution moves to take charge collected so that chemical reaction occurs, similar to those occurring at the anode, so the charge becomes neutral and the electron flow may continue to occur. This condition is often referred to as electrolysis (electro: electricity, lysis: digest).

An example of electrolysis is that when a salt solution of NaCl by electricity, the cathode reaction occurring is:
2H2O + 2e--> 2OH-+ H2
and hydrogen gas will be liberated from the cathode. Reaction at anode:
2H2O -> O2 + 4H + + 4e-
and oxygen gas will bubble from the anode. Positively charged Na + ions will react with the negative charge neutralization of the cathode, namely OH-and form NaOH, and the negatively charged Cl-ions will react with the positively charged anode neutralization results, namely H +, forming HCl. They will react to form H2O + NaCl NaCl so that the ionic liquid will return to form.

Please note that why not Na + gain electrons to become neutral, but instead of H2O, and not the Cl-which releases electrons to become neutral, but H2O is also, this is because Na + has oxidation state higher than H2O making it easier for H2O to capture electrons than Na + because it takes less energy. This is also true for Cl-that thinking about the high level reduktivitas.

Electrolytic conductor used in various industrial fields, including:
Battery
Fuel cell
Electroplating process
Electrolytic capacitor
Higrometer
Hydrometallurgical process
Making glass by melting the glass using electric currents

In our body, especially body fluids and blood, fluid balance is determined by the number of ions in the body which is calculated in units of electric charge as it affects the absorption of liquid dissolved in the intracellular or extracellular. Primary ions in the body are sodium, potassium, calcium, magnesium, chlorine, phosphoric acid, and carbonic acid. Known forms of life require a balance of electrolytes in the intracellular and extracellular because it involves the transportation of minerals, fluids, and nutrition. Electrolyte imbalance can affect hydration gradient of the body, blood pH, and muscle and nerve function. Berbadag mechanisms and physiological function of all living beings oeh applied in maintaining the balance in a controlled manner.

General properties of tin (Sn)

2011-08-22T06:14:00.000-07:00

Tin is a chemical element that has the symbol Sn and atomic number 50. Tin in English called a Tin. The word "Tin" is taken from the name of the Etruscan god "Tinia". Latin name of the lead is "Stannum" where the word is associated with the word "stagnum" which in English is synonymous with the word "dripping" which means to be a liquid / wet, the use of this word is connected with a metal tin that is easy to melt.
Ordinary tin is formed by nine stable isotopes. There are 18 other isotopes that diketahui.Timah a silvery white metal, with a low hardness, can be forged ("malleable"), has the properties of thermal and electrical conductivity are high, relatively soft, corrosion resistant and has a low melting point and have the structure crystal is high. If this structure is broken, a voice that is often called (weeping tin) when an element is bent.
Tin forms:

This element has 2 forms alotropik at normal pressure. When heated, lead gray (lead-alpha) with a cubic structure unchanged at 13.2 degrees Celsius into tin (tin beta) which has a tetragonal structure. When the tin is cooled to a temperature of 13.2 degrees Celsius, he slowly changed from white to gray. These changes are caused by impurities (impurities) such as aluminum and zinc, and can be prevented by adding antimony or bismuth. Gray tin has little usefulness. Tin can be polished very slippery and is used to cover other metals to prevent corrosion and chemical action. Thin layer of tin on the steel used to make food last.
Tin alloy is very important. Soft solder, bronze, Babbit metal, bell metal, white metal, alloy formation and phosphor bronze is an alloy containing some lead.
Tin can withstand sea water that has been distilled and tap water, but easily attacked by strong acids, alkali and acid salts. Oxygen in a solution can accelerate the action of chemicals such attacks. If heated in air, tin forms Sn2, slightly acid, and forming stannate salts with oxides. The most important salt is chloride, which is used as reducing agents. Tin salts are sprayed onto glass are used to make electrical conductor layer. This application has been used for the windshield that resists freezing. Most window glass is now made by floating molten glass on the molten tin to form a flat surface (Pilkington process).
Recently, a mixture of crystalline tin-niobium metal becomes superconducting at very low temperatures, making it as a construction material that promises a superconductive magnet. Magnet, which is made by tin-niobium wire weighs only a few pounds but with a small battery can produce a magnetic field similar to electromagnetic force of 100 tons carried by large power sources.

ž Sources Tin (Sn) on Earth
The minerals contained in the ore is generally the major minerals, namely cassiterite. Tin was not found in the element of free will on earth but is acquired from senyawaannya. Tin at present be obtained from the mineral cassiterite or tinstone. Cassiterite is a mineral of tin oxide SnO2, with a lead content ranging from 78%. Other examples of other sources of tin ore and received less attention than the sulfide mineral cassiterite is a complex that is stanite (Cu2FeSnS4) is a mineral complex of copper-tin-iron-sulfur and cylindrite (PbSn4FeSb2S14) is a mineral complex of timbale-tin-iron-antimony- sulfur are two examples of this mineral usually found in tandem with other metallic minerals such as silver.
Tin is an element of the 49th most abundant in the earth's crust where the tin has a content of 2 ppm compared with 75 ppm zinc, copper 50 ppm and 14 ppm for lead. Cassiterite is found in alluvial deposits / alluvium is soil or sediment that are not consolidated to form slabs of stone which can be settled at the bottom of the sea, rivers or lakes. Alluvium consists of various minerals such as sand, clay, and small rocks. Almost 80% of production is obtained from the alluvial tin / alluvium or the term secondary deposits. Chance to get 1 kg Cassiterite then about 7 tons of tin ore served until 8 / alluvial cassiterite be mined due to very low concentrations.
Tin earth unevenly spread but there are in one geographic area where there is an important resource in Southeast Asia including China, Myanmar, Thailand, Malaysia, and Indonesia. The results obtained are not so much of Peru, South Africa, UK, and Zimbabwe.
General properties of tin (Sn)
ü Lead a whitish metallic silver,
ü ductile and have a high crystalline structure,
ü In normal circumstances (13 - 160 ° C), the metal is shiny and malleable.
ü Lead is also not easily oxidized in air so that the stainless.
ü Found in many alloys, and used to coat other metals to prevent rust.

Physical properties of tin (Sn)
ü state of matter: Solid
ü Melting point: 505.08 K (449.47 ° F)
ü Boiling Point: 2875 K (4716 ° F)
ü Density: 7.365 g/cm3 (white Sn) 5.769 g/cm3 (gray Sn)
molar volume ü: × 10-6 m3/mol 16:29
ü Heat of vaporization: 295.8 kJ / mol
ü Heat of fusion: 7029 kJ / mol
ü Heat type: 27.112 J / molK
ü Heat of fusion: 7.03 kJ / mol
ü Vapor pressure: 5.78 E-21 Pa at 505 K
ü The speed of sound: 2500 m / s at 293.15 K

Mechanical properties of tin (Sn)
ü low-power appeal, approximately 2000 psi
ü Youngnya modulus is 5.9 to 7.8 x 10 ^ 6 psi
ü Strength Brinell Mohs 1.8 or 5.0 (1000 kg, 10 mm)

Chemical properties of tin (Sn)
ü atomic weight: 118 710 sma
ü density: 7.3 g/cm3
ü atomic radius: 145 (145) pm
ü covalent radius: 141 pm
ü The radius of the van der Waals: 217 pm
ü electron configuration: [Kr] 4d10 5s2 5p2
ü Electrons per energy level: 2, 8, 18, 18, 4
ü oxidation: 4.2, -4
ü Atomic number: 50
ü Number of mass: 118.71
ü electronegativity: 1.96 (scale Pauli)
ü 1st ionization energy: 708.6 kJ / mol
ü 2nd ionization energy: 1411.8 kJ / mol
ü 3rd ionization energy: 2943.0 kJ / mol
ü atomic radius: 140 pm
ü covalent radius: 139 pm
ü The radius van der Waals: 217 pm
ü Crystal structure: tetragonal (Sn white) cubic diamond (gray Sn)
ü thermal conductivity: 66.8 W / mK
ü lunah Tin is a metal, flexible, and the color is gray metallic. Tin is not easily oxidized and resistant to corrosion caused by the formation of tin oxide coating that inhibits further oxidation process. Tin is resistant to corrosion distilled water and sea water, but can be attacked by strong acids, alkalis, acids and salts. Oxidation process is accelerated by increasing the oxygen content in solution.
ü If the tin is heated in the presence of air it will form SnO2.
ü Tin exists in two allotropes of tin alpha and beta. Tin alfa-called gray tin and stable temperature below 13.2 ° C with covalent bonding structure such as diamond. While white beta tin and metal is stabilized at high temperatures, and is as a conductor.
ü Lead dissolved in HCl, HNO3, H2SO4, and some organic solvents such as acetic acid oxalic acid and citric acid. Tin is also soluble in strong base such as NaOH and KOH.
ü Tin generally have oxidation number +2 and +4. Tin (II) tend to have metallic properties and easily obtained from the dissolution of Sn in hot concentrated HCl.
ü Lead directly react with chlorine to form Sn (IV) chloride.
ü tin hydrides are stable only SnH4.

component analog video

2011-08-08T06:51:00.000-07:00

video signal that has been split into two or more components. In popular use, it refers to a type of analog video information that is transmitted or stored as three separate signals. Component video can be contrasted with composite video (NTSC, PAL or SECAM) in which all the video information is combined into a single line-level signal. Like composite, component-video cables do not carry audio and are often paired with audio cables.

component analog video is a format of video signal that takes the advancement from composite (1-signal) to S-Video (2-signals) one step further. It has separated luma (brightness) and chroma (color), but the chroma is also separated into two signals, red and blue. The result is a triple-headed RCA cable and an image cleaner than composite with less color bleeding that S-Video. Although common on newer DVD players, high-end HDTV's, and relatively modern CRT televisions, component video is very rare on older TV sets and VCR's.

component video systems, additional synchronization signals may need to be sent along with the images. The synchronization signals are commonly transmitted on one or two separate wires, or embedded in the blanking period of one or all of the components. In computing, the common standard is for two extra wires to carry the horizontal and vertical components ('separate syncs'), whereas in video applications it is more usual to embed the sync signal in the Y component ('sync on luminance').

Examples of international component video standards are:
RS-170 RGB (525 lines, based on NTSC timings, now EIA/TIA-343)
RS-343 RGB (525, 625 or 875 lines)
STANAG 3350 Analogue Video Standard (NATO military version of RS-343 RGB)

Radio Frequency

2011-08-08T06:23:00.000-07:00

The term Radio Frequency (RF or rf) refers to the electromagnetic field that is generated when an alternating current is input to an antenna. This field, also called an RF field or radio wave, can be used for wireless broadcasting and communications over a significant portion of the electromagnetic radiation spectrum -- from about 9 kilohertz (kHz) to thousands of gigahertz (GHz). This portion is referred to as the RF Spectrum. As the frequency is increased beyond the RF spectrum, electromagnetic energy takes the form of infrared (IR), visible light, ultraviolet (UV), X rays, and gamma rays.

Many types of wireless devices make use of RF fields -- radio, television, cordless and cellular telephones, satellite communication systems, and many measuring and instrumentation systems used in manufacturing. Some wireless devices, such as remote control boxes and cordless mice, operate at IR or visible light frequencies. The RF spectrum is divided into several ranges, or bands. Each of these bands, other than the lowest frequency segment, represents an increase of frequency corresponding to an order of magnitude (power of ten). The chart at the top of the page depcits the eight bands in the RF spectrum, showing frequency and bandwidth ranges.

diode bridge

2011-08-06T21:51:00.000-07:00

Silicon diode is a diode bridge is assembled into a bridge and packed into a single unit component. In the market sold various forms of the diode bridge with a variety of capacities. The size of the main bridge diodes are voltage and amperage maximum. Diode bridge rectifier is used as the power supply.

diode bridge is an arrangement of four (or more) diodes in a bridge circuit configuration that provides the same polarity of output for either polarity of input. When used in its most common application, for conversion of an alternating current (AC) input into direct current a (DC) output, it is known as a bridge rectifier. A bridge rectifier provides full-wave rectification from a two-wire AC input, resulting in lower cost and weight as compared to a rectifier with a 3-wire input from a transformer with a center-tapped secondary winding.

One complete cycle of operation will be discussed to help you understand how this circuit works. We have discussed transformers in previous modules in the NEETS series and will not go into their characteristics at this time. Let us assume the transformer is working properly and there is a positive potential at point A and a negative potential at point B. The positive potential at point A will forward bias D3 and reverse bias D4. The negative potential at point B will forward bias D1 and reverse bias D2. At this time D3 and D1 are forward biased and will allow current flow to pass through them; D4 and D2 are reverse biased and will block current flow. The path for current flow is from point B through D1, up through RL, through D3, through the secondary of the transformer back to point B. This path is indicated by the solid arrows. Waveforms (1) and (2) can be observed across D1 and D3.

wave

2011-08-06T21:31:00.000-07:00

In electromagnetic radiation, the energy of the wave is related to both the frequency (nu) and wavelength (lambda) of the wave, in the following forms:
E = h nu = hc / lambda

The table below shows the approximate wavelength, frequency, and energy ranges for different types of electromagnetic waves. An illustration of the spectrum is in the image to the right, which can be examined closer by clicking on it.

Notice that there is some overlap. For example, the terahertz waves (which are just now being studied and found to have intriguing properties) really lie just on the border of the microwave and infrared waves. Also, some depictions show an overlap between infrared & microwave, ultraviolet & x-ray, and x-ray & gamma rays, so these ranges are somewhat flexible at the boundaries. These values (except for the terahertz, which I calculated from other sources) came from NASA, so I figure they're close enough.

A wave is a disturbance traveling through space, transferring energy from one point to the next without permanently changing space itself. Physicists have depicted a wave graphically as the passage of such a disturbance over time.

electromagnetic radiation

2011-08-06T20:45:00.000-07:00

The wave theory of electromagnetic radiation was formalized in the 1800s by James Clerk Maxwell, who realized that such energy was a disturbance of time-varying electric and magnetic fields propagating through space, which fit the wave equation. He organized a series of equations (named, oddly enough, Maxwell's equations) to describe this wave motion.

Einstein's later work with the photoelectric effect revealed that electromagnetic waves carry quantized energy in the form of photons, but the wavelike properties remain in most circumstances and therefore a reformulation of Maxwell's equations are still used today to describe electromagnetic waves.

Electromagnetic radiation, the larger family of wave-like phenomena to which visible light belongs (also known as radiant energy), is the primary vehicle transporting energy through the vast reaches of the universe. This interactive tutorial explores the classical representation of an electromagnetic wave as a sine function, and enables the visitor to vary amplitude and wavelength to demonstrate how this function appears in three dimensions.

Electromagnetic radiation (often abbreviated E-M radiation or EMR) is a form of energy exhibiting wave-like behavior as it travels through space. EMR has both electric and magnetic field components, which oscillate in phase perpendicular to each other and perpendicular to the direction of energy propagation.

Turbine Engine Diagnostics (TED)

2011-08-06T06:48:00.000-07:00

Turbine Engine Diagnostics (TED) is a diagnostic expert system to aid the Ml Abrams tank mechanic find and fix problems in the AGT-1500 turbine engine.
aircraft gas turbine engine diagnostic system, comprising:a computing device comprising a port configured to receive a removable memory device, the computing device operable to retrieve engine performance data stored on the removable memory device, the engine performance data representative of a plurality of aircraft gas turbine engine parameters, the computing device further operable to run engine diagnostics based on the retrieved engine performance data; andan engine controller comprising:a processor coupled to receive the engine performance data and configured to (i) generate and supply engine control signals based, at least in part, on the engine performance data and (ii) selectively transmit at least a portion of the engine performance data for storage;a fixed memory device in operable communication with the processor to receive and store the engine performance data selectively transmitted by the processor, the fixed memory device fixedly coupled to a fixed-memory mount; andthe removable memory device in operable communication with the processor to receive and store the engine performance data selectively transmitted by the processor, the removable memory device non-fixedly coupled to a removable memory mount in a manner that allows the removable memory device to be hand-removable from the removable memory mount and inserted into the port of the computing device.

Gas turbine engines are widely used in different fields for generate energy. They are commonly used in aircrafts. If you watch a huge passenger aircraft, you can see the gas turbine engines are either hanging on the wing section or tail section. Those power plants gives enough energy to generate thrust which finally result the aircraft fly.

gas turbine engine, comprising the steps of:receiving, in an engine controller, engine performance data representative of a plurality of aircraft gas turbine engine parameters;storing at least a portion of the received engine performance data in a fixed memory device that is fixedly coupled to a fixed-memory mount in the engine controller; andstoring the at least a portion of the received engine performance data in a removable memory device that is non-fixedly coupled to a removable memory mount in the engine controller in a manner that allows the removable memory device to be hand-removable from the removable memory mount;removing the removable memory device from the removable memory mount in the engine controller;inserting the removable memory device in a port of a computing device that is not coupled to the engine controller;retrieving the engine performance data stored on the removable memory device; andanalyzing the performance of the aircraft gas turbine engine based on the retrieved engine performance data.

Step Recovery Diode (SRD)

2011-08-06T06:12:00.000-07:00

Diodes are one of passive electronic components. Diodes have two pole pieces of leg and foot anode cathode. Diodes made from semi-conductor type P and N type semi-conductors that are connected together.

Due to the nature of the diode that works as a conductor if we give forward bias and works as an insulator in reverse bias, then .. often used as a rectifier diode (rectifier) alternating current. Examples of its use is on the circuit adapter, DC power supply (Power Supply DC) and so on.

To determine the diode is in good condition or damaged we can measure it using a multimeter or ohmmeter. Because nature is only able to drain diode direct current only, the installation of the multimeter to the diode must be done as follows:
Positive terminal (+) multimeter in diode cathode connected to the leg.
Negative terminal (-) multimeter diode anode connected to the leg.

Step Recovery Diodes have relatively little capacitance change under reverse bias and are used for higher efficiency applications. These diodes do not require idler circuits to enhance efficiency. The use of these diodes results in:
High Efficiency
High and Low Order Multiplication
Narrow Bandwidth
Comb Generation

Absolute Maximum Ratings
Storage Temperature: -65C to +200C
Operating Temperature: -65C to + 175C

Step Recovery Diode (SRD) has long been used to build high order frequency multiplier circuits. An approximate design procedure for the SRD frequency multiplier can be found in Hewlett Packard application note 920.

While this 1960's era technology is still in fairly wide use, there's still no other computer program to aid in the design process and no nonlinear model of a true SRD known to the author. At least one manufacturer of step recovery diodes does publish approximate SPICE models of their parts, though SPICE cannot represent the diode's transition time.

Step-Recovery Diodes By reducing the doping level near the junction of the plant can make the step-recovery diode devices that use charge storage. During the forward conduction diodes behave as usual and when dibias diode reverse diode conduction while the layer is being set up and then emptying all of a sudden reverse flow becomes zero. In these circumstances as if the diode suddenly snapped open (snaps open) such as switches, and this is why the step-recovery diode is often called the snap diode. Step-recovery diodes are used in pulse and digital circuits to produce a very rapid pulse. Snap-off that suddenly can result in switching on-off less than 1 ns. This particular diode is also used in frequency multipliers.

Hi-Fi

2011-07-22T20:42:00.000-07:00

- - - LPF DC Operating Point ---
V(supply): 6 V
V(out): 2.0419 V
V(d): 5.35688 V
Ic(Q5): -0.645428 mA
Id(J1): 1.04209 mA

The audio filter circuit that I designed in did not use the notch but is an S-K (Sallen-Key) 3 pole design. It could be tweaked a bit for the European station spacing, but is probably okay without any design change as it is. The filter compromise reduces noise at the expense of bandwidth. Most cheap radios have inadequate filtering, erring on the side of too much in the case of AM tuners (about 3KHz. roll off) to too little in the case of cheap radios. I erred on the side of (perhaps) too little, in order to include more bandwidth so that the audio upper spectrum would be present if broadcast. I'm relying on the sharper cutoff of a 3-pole Chebyshev filter to help more with noise while allowing "flat" (has some peaking) response to 6.6KHz. Listening revealed that I could get a little more by allowing 10KHz. bandwidth, but the noise was much more noticeable. The chosen bandwidth works with the 9KHz. European. channel spacing as well.
Note that I used a BF244B FET in the circuit, but a 2N4416 for the simulation. The two devices have very close to the same characteristics. Also, the filter works just about as well
with some standard components for C4 and C2. Here are the new values:
C4 old=15nF, new=10nF
C2 old=39nF, new=33nF
The resulting filter response looks very much the same, but the filter gains some bandwidth. These parts are easier to get, but 5% tolerance would be advised for C2, C3, and C4.
I later discovered that the JFET-BJT follower circuit works better when the drain resistor (R14 in the simulation, R18 on the full schematic) is increased to 1K ohm. I made this change when I found that one of my circuits had more distortion than expected. The FETs have a lot of variation, and increasing the resistor value makes the circuit more tolerant over the full range of possible BF244B FET characteristics.

I have to say that this tuner gives me "near FM" quality on AM. The few distractions come from static which AM is famous for, and can't be eliminated, but other than this, it sounds
great.

Here is a Hi-Fi AM superhet receiver using the linear detector discussed above. The whole thing fits on a small PC board pictured right. The linear detector is on the part of the PC board in the foreground, and the TO220 package to the left of it is an LM317 voltage regulator for the 6V power rail.
The front end circuit is shown below. It uses the NXP / Philips NE602 double-balanced mixer chip; or, as here, the SA612, which is a lower cost version.

C5 and C6 were NOT fitted in the final build. The NE602 / SA612 has differential input and output, but I wanted the option of running single ended in case the ground would help. The filter formed by the 21.5 ohm resistor and 10uH choke keeps feedback from occurring through the power supply rail, which will cause the receiver to oscillate if those components are not present. C17 is part of that filter too. The oscillator coil was used "inverted" from what is normal. The tap is closest to the "hot" end of the coil, since the SA612 oscillator doesn't need much "step-up" from the transformer. In fact, the resistor is to reduce the drive somewhat, to keep the oscillator amplitude from being too much.
To avoid stability problems, the "loopstick" antenna should preferably be shielded from the rest of the circuit. Placing the circuit in a metal box, with the loop antenna outside is optimum. My implementation had the loop antenna attached to the PC board, which allows some feedback through the receiver of the 455KHz. signal and hence some "tweet".
The IF amplifier is shown on the complete Circuit Schematic (GIF image, click to open it in a separate browser window) and is discussed in more detail later. Note that the Toko IF transformers have an internal resonating capacitor, which is not shown on the diagrams. The detector and audio output part of the circuit is shown below.

Q7, Q5, Q6, and Q8 comprise the detector circuit. Q9 and Q10 form a unity gain buffer, and 3-pole active low pass filter that cuts off at 7KHz. (12 dB down at 10KHz.). Q9 is a BF244B
N channel JFET. The IF amplifier has AGC driven by the detector output at the top of R16.

DDS AD9851

2011-07-22T20:07:00.000-07:00

DDS AD9851 for the HF + 6M Transceiver Radio

Direct Digital Synthesis (DDS) is a frequency generator with digital synthesis using a reference clock. The principle is no different from the PLL (phase locked loop), only the PLL uses a VCO to generate the frekewensi. In other words DDS = digital PLL.
DDS has been widely applied to radio transceiver, especially at the low end segment of the factory transceiver. Medium segment of mid and high end, still using the PLL, with consideration, for now the PLL is still better than DDS.
DDS uses firmware homebrew made by CV.Niras (VU3CNS) with some modifications on the hardware. In this project I use the AD9851. AD9850 can also be used, but the 6x multiplier it should be disabled, and use max 120MHz reference clock.

Specifications:
1. Using the AD9851 and 2x 16F628A
2. 25MHz reference clock, 6x multiplier
3. Generating frequency from 0-60Mhz
4. Having VFO-A, VFO-B, and RIT
5. 20 programs have memory to store the VFO-A and VFO-B
6. Mode control has a LSB, USB, CW, and AM
7. Having control for BPF and LPF for the entire nine HF bands (160m, 80m, ...., 10m)
8. Input data using a mechanical encoder and numeric pad.
9. Has 6 control buttons Save / Memory, Split / VFO A = B / RIT, Lock / Mode, Step, and Calibration
10. RF output is around 20mW (MAV-11)
11. Display frequency: direct, LO-IF, or IF-LO.

Aside from being a Local oscillator in radio communications, DDS is also used as signal generators, function generators, etc..
DDS IC soldering into the PCB requires precision and patience are very high. It is small and the distance between the feet is very tight. I failed 3 times already, which means I lost 3 pieces of PCB and 3 IC DDS, mahaaal experience.
To make it easier for soldering, and assemble his DDS IC, I bought a 28 pin SOIC to DIL adapter PCB (U.S. $ 2 + ongkir), and re-designing its layout pcb with 28 pin DIL.
Since the AD9851 output signal is only 0.5mW, and I plug 60Mhz LPF and MAV-11 amplifier. Signal is strong enough, and enough to drive the diode mixer level 7 or 10.

Hi-Fi audio

2011-07-21T05:02:00.000-07:00

Hi-Fi audio
This circuit is a simple audio amplifier based on TDA1910 IC. This circuit will deliver 10W power output if used 8 ohm loudspeaker and powered with 24V DC supply.
Note

* Use 18-24V DC for powering the circuit.
* A proper heat sink is necessary for the IC.

The TDA 1910 IC is a monolithic integrated circuit inmultiwatt package, intended for use in Hi-Fi audio power applications, as high quality TV sets. The TDA 1910 meets the DIN 45500 (d = 0.5%) guaranteed output power of 10W when used at 24V/4W. At 24V/8W the output power is 7W min.

Maximun ratings TDA 1910 IC
* Supply voltage 30 V
* Output peak current (non repetitive) 3.5 A
* Io Output peak current (repetitive) 3.0 A
* Input voltage 0 to + Vs V
* Differential input voltage ± 7 V
* Power dissipation at Tcase = 90°C 2 0W
* Storage and junction temperature -40 to 150 °

PIR

2011-07-21T04:50:00.000-07:00

A normal electronic security system will have a transmitter and a receiver. The transmitter sends out an IR laser and this will be received by the receiver. When an intruder walks past the device, the IR beam is cut and thus the alarm is activated. But, this system has some major disadvantages like limited range and poor line of sight. These disadvantages are eliminated through the PIR sensor circuit explained below.
Working

Instead of infrared or laser transmitters and receivers, PIR (Passive Infrared Radial) sensors are used in this circuit. The sensor is basically a pyroelectric device. When the device is exposed to infrared radiation, it generates an electric charge. The device is made of crystalline material. According to the change in the amount of infrared striking the element, there will be a change in the voltages generated, which is measured by an on-board amplifier.

The infrared light explained here refers to the light radiating from all objects in its field of view. The reason for not having a transmitter and receiver is that the device does not emit one, but only accepts the energy emitted from objects above absolute zero in the form of radiations. Thus the temperature will be different for a human working past a sensor, and that of a wall right in front of it. Thus the word “passive” is used in PIR to explain that it does not emit a radiation and receive it, but instead accepts the incoming infrared radiation passively.

audio power

2011-07-21T04:22:00.000-07:00

TDA2009 is an audio power amplifier double hi-fi in multiwatt package, especially developed for applications of high quality stereo. That application is the amplification in bridge, where it is used the two amplifiers interns of the tda2009. The good of the series of circuits integrated tda is that are component electronic easy to find at the electronics stores. Although some can find the potency of 18 watts little rms, be sure that many of those audio equipments industrialized they use that type of integrated circuit and they speak in potencies of up to 100 watts. That circuit supplies a potency even considerable to hear music.

LM2575

2011-07-15T20:52:00.000-07:00

The switching regulator power supply used LM2575-5.0 on this schematic. You can make the stable voltage by using the 3 terminal regulator like LM317. However, because the output electric current and the inputted electric current are the same approximately, the difference between the input electric power (The input voltage x The input electric current) and the output power (The output voltage x The output current) is consumed as the heat with the regulator. Because it is, the efficiency isnt good.

The LM2575 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version.

Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator.

The LM2575 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in many cases no heat sink is required.

ZN414 IC

2011-07-15T19:52:00.000-07:00

At this point it is worthwhile downloading the data sheets. Search for data on not just the ZN414, but the other clones as well.
One of the Ferranti sheets is available here on the Jaycar site.
Briefly, the tuned circuit is fed straight into the IC. There is no need for a tapped coil due to the 4M input impedance. Looking at the internal diagram of the TA7642, we can see this is a result of using an emitter follower at the input pin. Four stages of amplification and an active detector result in a gain of about 72dB which is high enough to give good results with no external aerial. In fact, gain is not too far off an average superhet using the same size aerial rod. The .1uF at the output pin is for RF bypassing, and in conjunction with Ragc, determines the audio bandwidth. The data sheet shows how this capacitor value is calculated. Apparently, the higher the value, the more gain can be had. This would make sense as RF bypassing would be improved with an increase in capacitance value.
The DC at the output pin varies with signal strength and this is used for AGC. The 100K and .01uF are the usual time constant to remove audio fluctuations. In addition, the .01uF is also the RF bypass for the earthy end of the aerial coil and tuning condenser. Gain of the IC is thus controlled by the DC at the input pin.
I have seen some circuits incorrectly drawn, particularly with the LMF501T clone, where the 100K has been connected directly to the input pin, along with the .01uF for DC isolation of the aerial coil. While it would work to a degree, and the DC conditions are correct, the problem is 100K is effectively shunted across the aerial coil and will result in loss of gain and selectivity.
It is important that the tuned circuit is the only thing connected to the input pin.

My interest had been rekindled of late as Dick Smith was selling MK484's at half price. Knowing that they are slowly getting rid of components, I went and stocked up with a lifetime supply. I have known about the ZN414 for years; for a long time the Dick Smith catalog had provided a circuit (EA May 1974) in the back of their catalog.
The ads for the device proclaimed such virtues as "equivalent to a ten transistor radio". Ten transistors it may have, but it actually has only four stages of RF amplification. This is about the practical limit before instability would set in. The other transistors are used for the detector, AGC, impedance matching, and stabilisation.

The first time I actually used the ZN414 was with the Funway kits back in 1981. In the Funway 1 volume was the "Beer Powered Radio" which was the standard ZN414 circuit driving a crystal earphone but powered from a homemade battery using beer as the electrolyte. A modification was shown to run the circuit from a 9V battery instead, which needless to say is the version I built. In Funway 2 was the "Pocket Transistor Radio" which drove a magnetic earphone and ran off a 9V battery. Its performance was very poor for two reasons. Firstly the method of obtaining the supply for the ZN414 was a bodge and resulted in instability, and secondly, the 9V battery pressed up against the ferrite rod ruined the signal pickup. This particular circuit was the same as EA's August 1979 design, except for the modification for 9V operation.

During the mid to late 80's when I was learning about solid state, I experimented with many different ZN414 circuits and associated audio amplifiers. I used to demonstrate to some of my fellow students a ZN414 receiver with a two transistor amplifier driving a speaker that I'd build on a breadboard from time to time. I recall listening to 2SM during one of our programming classes on such a set. Soon after, I went off listening to AM as a results of changes to formats and stations migrating to FM. So, the ZN414 became dormant in my designs until recently, now that I'm mainly listening to AM again.
Also was the fact I'd accumulated a few of the $2 shop radios using the ZN414 clones.

An AM portable radio receiver made from the ZN414 IC. The ZN414 ic has now been replaced by the MK484 which is identical in performance and pinout.

Notes:
Designed around the popular ZN414 IC this receiver covers the medium wave band band from approximately 550 to 1600 KHz with the values shown. The coil and tuning capacitor may be taken from an old MW radio to save time. The ZN414 IC, has now been replaced by the MK484. The integrated circuit is a 3 pin, tuned radio frequency circuit, and incorporates several RF stages, automatic gain control and an AM detector. It is easily overloaded and the operating voltage of th IC is somewhat critical to achieve good results.

In this circuit a small voltage regulator is built around the BC108B transistor, four 1N4148 diodes, the 2k7 and 10k preset resistor and the 820R resistor. The 10k pot acts as a selectivity control for the whole receiver, controlling the operating voltage for the ZN414 (or MK484). If you live in an area that is permeated with strong radio signals, then the voltage may need to be decreased. I found optimum performance with a supply of around 1.2 volts.

The audio amplifier is built about an inverting 741 op-amp amplifying circuit. Extra current boost is provided using the BC109C / BC179 complementary transistor pair to drive an 8 ohm loudspeaker. The voltage gain of the complete audio amplifier is around 15. The audio output of the complete receiver is really quite good and free from distortion. I may provide a sound sample later. Click here to see a picture of my prototype. I used a small wooden enclosure and the complete tuning assembly from an old radio.

IC-7800

2011-07-15T19:09:00.000-07:00

The IC-7800 uses durable mechanical relays for BPF switching instead of non-linear semi-conductors, like switching diodes which can cause distortion. The mechanical relay reduces secondary distortion at the primary stage of signal processing.

The IC-7800’s somewhat familiar looks will remind many HF operators of the IC-781. The IC-781 set benchmarks back in the 1980’s as that generation’s ultimate HF transceiver. Some of today’s operators still feel the IC-781 is the pinnacle in amateur radio design. They have not seen the IC-7800. It takes amateur radio to a whole new level of performance. The IC-7800 will be viewed as the pinnacle radio for years to come.

The IC-7800 is an artistic fusion of over 40 years analog RF circuit development expertise and cutting-edge digital technology. The result is TWO identical receivers with 110dB dynamic range, +40dBm 3rd order intercept point, and unmatched DSP technology in the HF bands something that has never been achieved in Ham radio! Simply put, Icom has developed the ultimate Amateur HF transceiver.

SCR

2011-07-15T05:20:00.000-07:00

A rudimentary test of SCR function, or at least terminal identification, may be performed with an ohmmeter. Because the internal connection between gate and cathode is a single PN junction, a meter should indicate continuity between these terminals with the red test lead on the gate and the black test lead on the cathode like this.

All other continuity measurements performed on an SCR will show "open" ("OL" on some digital multimeter displays). It must be understood that this test is very crude and does not constitute a comprehensive assessment of the SCR. It is possible for an SCR to give good ohmmeter indications and still be defective. Ultimately, the only way to test an SCR is to subject it to a load current.

If you are using a multimeter with a "diode check" function, the gate-to-cathode junction voltage indication you get may or may not correspond to what's expected of a silicon PN junction (approximately 0.7 volts). In some cases, you will read a much lower junction voltage: mere hundredths of a volt. This is due to an internal resistor connected between the gate and cathode incorporated within some SCRs. This resistor is added to make the SCR less susceptible to false triggering by spurious voltage spikes, from circuit "noise" or from static electric discharge. In other words, having a resistor connected across the gate-cathode junction requires that a strong triggering signal (substantial current) be applied to latch the SCR. This feature is often found in larger SCRs, not on small SCRs. Bear in mind that an SCR with an internal resistor connected between gate and cathode will indicate continuity in both directions between those two terminals

If an SCR's gate is left floating (disconnected), it behaves exactly as a Shockley diode. It may be latched by breakover voltage or by exceeding the critical rate of voltage rise between anode and cathode, just as with the Shockley diode. Dropout is accomplished by reducing current until one or both internal transistors fall into cutoff mode, also like the Shockley diode. However, because the gate terminal connects directly to the base of the lower transistor, it may be used as an alternative means to latch the SCR. By applying a small voltage between gate and cathode, the lower transistor will be forced on by the resulting base current, which will cause the upper transistor to conduct, which then supplies the lower transistor's base with current so that it no longer needs to be activated by a gate voltage. The necessary gate current to initiate latch-up, of course, will be much lower than the current through the SCR from cathode to anode, so the SCR does achieve a measure of amplification.

This method of securing SCR conduction is called triggering, and it is by far the most common way that SCRs are latched in actual practice. In fact, SCRs are usually chosen so that their breakover voltage is far beyond the greatest voltage expected to be experienced from the power source, so that it can be turned on only by an intentional voltage pulse applied to the gate.

Zener breakdown

2011-07-12T05:36:00.000-07:00

The Zener diode is particularly interesting in the way that it operates. There are actually two mechanisms that can cause the breakdown effect that is used to provide the voltage reference effect:
Zener breakdown: Although the physics behind the effect is quite complicated, it can be considered that this effect occurs when the electric field within the semiconductor crystal lattice is sufficiently high to pull electrons out of the lattice to create a hole and electron. The electron then moves under the influence of the field to provide an electric current.

Impaction ionisation: Again this effect occurs when there is a high level of electric field. Electrons are strongly attracted and move towards the positive potential. In view of the high electric field their velocity increases, and often these high energy electrons will collide with the semiconductor lattice. When this occurs an electron may be released, leaving a hole. This newly freed electron then moves towards the positive voltage and is accelerated under the high electric field, and it to may collide with the lattice. The hole, being positively charged moves in the opposite direction to the electron. If the field is sufficiently strong sufficient numbers of collisions occur so that an effect known as avalanche breakdown occurs. This happens only when a specific field is exceeded, i.e. when a certain reverse voltage is exceeded for that diode, making it conduct in the reverse direction for a given voltage, just what is required for a voltage reference diode.

It is found that of the two effects the Zener effect predominates above about 5.5 volts whereas impact ionisation is the major effect below this voltage.

The two effects are affected by temperature variations. This means that the Zener diode voltage may vary as the temperature changes. It is found that the impact ionisation and Zener effects have temperature coefficient in opposite directions. As a result Zener diodes with reverse voltages of around 5.5 volts where the two effects occur almost equally have the most stable overall temperature coefficient as they tend to balance each other out for the optimum performance.

Low Drop-out

2011-07-12T04:53:00.000-07:00

Important considerations when selecting a voltage regulator include: 1) the desired output voltage level and its regulation capability; 2) the output current capacity; 3) the applicable input voltages; 4) conversion efficiency (Pout/Pin); 5) the transient response time; 6) ease of use; and if applicable, 7) the ability to step-down or step-up output voltages. In switch-mode regulators, the switching frequency is also a consideration.

There are several types of voltage regulators, which may be classified in terms of how they operate or what type of regulation they offer. The most common regulator IC is the standard linear regulator. A typical linear voltage regulator operates by forcing a fixed voltage at the output through a voltage-controlled current source. It has a feedback mechanism that continuously adjusts the current source output based on the level of the output voltage. A drop in voltage would excite the current source into delivering more current to the load to maintain the output voltage. Thus, the capacity of this current source is generally the limiting factor for the maximum load current that the linear regulator can deliver while maintaining the required output level. The amount of time needed for the output to adjust to a change in the input or load is the transient response time of the regulator.

The feedback loop used by linear regulators need some form of compensation for stability. In most linear regulator IC's, the required feedback loop compensation is already built into the circuit, thereby requiring no external components for this purpose. However, some regulator IC's, like the low-dropout ones, do require that a capacitor be connected between the output and ground to ensure stability. The main disadvantage of linear regulators is their low efficiency, since they are constantly conducting.

The switching voltage regulator is another type of regulator IC. It differs from the linear regulator in the sense that it employs pulse width modulation (PWM) to regulate its output. The output is controlled by current that is switched at a fixed frequency ranging from a few Hz to a few kHz but with varying duty cycle. The duty cycle of the pulses increase if the output of the regulator needs to supply more load current to maintain the output voltage and decreases if the output needs to be reduced. Switching regulators are more efficient than linear regulators because they only supply power when necessary. Complexity, output ripples, and limited current capacity are the disadvantages of switching regulators.

There is also a group of regulator IC's known as Low Drop-out (LDO) regulators. The drop-out voltage is the minimum voltage across the regulator that's required to maintain the output voltage at the correct level. The lower the drop-out voltage, the less power is dissipated internally within the regulator, the higher is the regulation efficiency. In LDO regulators, the drop-out voltage is typically just about 0.6 V. Even at maximum current, the drop-out voltage increases to just about 0.7-0.8 V.

voltage regulator

2011-07-12T04:25:00.000-07:00

Typically, electronic voltage regulators employ a feedback network, where a high-gain amplifier compares a fraction of the load voltage VL/k with a constant reference Vref. Any difference between these two voltages is amplified and used to control a series pass device in a manner whereby this difference is minimized. For an ideal amplifier with zero offset and infinite voltage gain, the difference is reduced to zero and the ideal relationship of Eq. (2) is realized. See also Feedback circuit.

The wide range of applications for electronic voltage regulators has led to the development of these circuits in fully monolothic integrated circuit technology, where all or most of the required circuit components are realized on a single chip of silicon. Offering various output current and voltage ratings, and output voltages of either positive or negative polarity, several commercial regulator integrated circuits are now available to suit the requirements of most applications. The designs of these regulators have matured and have become rather sophisticated. In addition to implementation of the high-gain feedback amplifier, the series pass element, and an accurate voltage reference, all on a single silicon die, built-in protection against overload conditions (such as output short circuits and excessive operating temperature) is now standard. Novel circuit-design, processing, and packaging techniques have been developed and implemented to achieve increased accuracy, temperature stability, efficiency, reliability, and power-handling capability, while reducing package size and cost. See also Integrated circuits.

Voltage regulators are used on distribution feeders to maintain voltage constant, irrespective of changes in either load current or supply voltage. Voltage variations must be minimized for the efficient operation of industrial equipment and for the satisfactory functioning of domestic appliances, television in particular. Voltage is controlled at the system generators, but this alone is inadequate because each generator supplies many feeders of diverse impedance and load characteristics. Regulators are applied either in substations to control voltage on a bus or individual feeder or on the line to reregulate the outlying portions of the system. These regulators are variable autotransformers with the primary connected across the line. The secondary, in which an adjustable voltage is induced, is connected in series with the line to boost or buck the voltage. See also Autotransformer; Electric distribution systems; Electric power substation.

Voltage regulators are used on rotating machines in power generation applications to automatically control the field excitation so as to maintain a desired machine output voltage. Rotating machines, both small (down to 1 kW) and large (up to 1,000,000 kW), are the predominant means of power generation throughout the world, and voltage regulators of varying design and sophistication are employed on most of them. Even ac generators (or alternators) in automotive applications employ voltage regulators utilizing similar principles.

How it Works and Functions Each transformer:

2011-07-10T21:03:00.000-07:00

Understanding the transformer or transformers in brief is to energize the electromagnet components or electrical power from high voltage to low voltage or vice versa, with equal frequency. When utility power is interrupted, the officer will check the transformer is working. why transformer needed? because it usually needs a tool that does not allow the use it supply nets - nets, say so many companies are to importtechnology from outside or country of origin, say for example that Japan will open a factory in Indonesia of course technological resources ranging from machinery and other equipment should take dong because Indonesia did not have in Japan when the voltage was 110V instead of 220V was used in Indonesia like-what's the solution? step-down transformer is used of voltage 110V U.S. $ 220 used to be a simple understanding of the transformer is a device used to change the amount of voltage can be increased or scaled back
Understanding power transformer / power transformer

Power transformer is an electrical power equipment that serves to channel the energy / power from high voltage to low voltage or vice versa (transform voltage) in general terms that the power transformer
To facilitate the supervision of the operation of the transformer can be divided into: large Transformer, Trafo medium, small transformers.

How it Works and Functions Each transformer:

The main part
- The core of iron
Iron core serves to facilitate the flux path, caused by electric current through the coil. Made of thin steel plates are insulated to reduce heat (as the iron losses) caused by the "Eddy Current".
- The coil transformer

Some insulated wire wrapped to form a coil. The coil is well insulated against the iron core and to the other coil with solid insulation such as cardboard, pertinax and others. Generally there is a coil on the transformer primary and secondary. When the primary coil is connected to the voltage / alternating current in the coil then the flux that induce a voltage arises, when the secondary circuit is closed (the load circuit) then the current will flow in the coil. So the coil as a means of transformation of voltages and currents.

- The coil tertiary
Tertiary coil voltage needed to obtain a tertiary or for other needs. For both purposes, the tertiary coil is always connected to the delta. Tertiary coil is often used also for connecting auxiliary equipment such as condenser Synchrone, shunt capacitors and shunt reactors, however, not all of the power transformer has a tertiary coil.

- Transformer oil
Most of the power transformer core and coils immersed in the oil-transformer, transformer-especially large-capacity power transformer, because it has the properties of transformer oil as a heat transfer medium (circulated) and is also as insulation (high breakdown voltage power) that serves as cooling and insulation media

There are at least three causes damage to the transformer resulting in outages at the customer channel. About 30 percent are caused by the reduced volume of lubricating oil to make fast heat transformer and then burned, 24 percent due to lightning strikes, and seven percent due to excess pressure. The rest, can be caused by, for example, components that are old and should replaced and overloaded.

To overcome such defects, electrical officer will identify the cause first. If the cause is the lubricant that is reduced, we can be sure a leak on the fins, body, tap expenses, cover packing up, packing bushing and tap changer that must be patched. The officer just add oil or lubricating oil which has been reduced due to the leak until a stable size. If t / Afo damaged by lightning and overload, can be overcome by mutations transformer

Transformer isolation and its use

2011-07-10T20:45:00.000-07:00

isolation transformer is an isolation transformer is designed to overcome the problems associated with internal insulation to ground reference. It is built with two rolls of Faraday isolation between primary and secondary windings.

isolation transformer secondary winding having the same amount with the primary winding, so the secondary voltage is equal to the primary voltage. But in some designs, the secondary winding is made a bit more to compensate for the loss. This transformer serves as insulation between the two prop. For audio applications, the transformer of this type have been largely supplanted by the coupling capacitor.

When installed properly, insulation, closest to the primary winding, is connected to ground power supply and the isolation of the most common close to the secondary winding is connected with the isolation circuit to be isolated. The use of two shields in the construction of an isolation transformer for the transfer of high-frequency noise, which will usually be incorporated in the transformer

Both shields provide more effective isolation of primary and secondary circuits by also isolating their reasons. Transformer isolation adds the third capacitance between the two Faraday shield, which can allow high frequency noise coupling between the base system. However, increasing the separation between the two Faraday shield to minimize this capacitance is usually the third. In addition, the effect of the dielectric shield plus separation increased significantly reduce the capacitance roll-between between the rolls.

Transformer isolation and its use

isolation transformer is extensively used in medical equipment, telecommunications equipment, remote control equipment, computers & peripherals, CNC machines, analytical instruments, etc.
Losses in the transformer

Copper losses. I2.R copper losses in the windings caused by the resistance of copper and electrical currents flood.

Coupling losses. Losses incurred due to the primary-secondary coupling is not perfect, so not all the induced magnetic flux cutting the coil primary secondary. These losses can be reduced by rolling in multi-layered winding between primary and secondary.

Capacity loss is wild. Losses caused by wild capacity contained in the winding-winding transformer. These losses greatly affect the efficiency of the transformer for high frequency. These losses can be reduced by rolling the primary and secondary windings are semi-random (winding banks).

Hysteresis losses. Losses that occur when the primary AC current U-turn. Due to core transformer can not change the direction of the magnetic flux immediately. These losses can be reduced by using low reluctance core material.

Skin effect losses. As with other current-carrying conductor alternating, currents tend to flow on the surface of the conductor. This enlarges the capacity loss and also increase the relative resistance of the coil. These losses can be deducted by using Litz wire, the wire consists of several small wires are mutually insulated. For the radio frequency used geronggong wire or thin
copper sheet instead of regular wire.

Eddy current losses (currents megrim). Losses caused by emf input that causes the current in a magnetic core that is against the change of magnetic flux that generates an emf. Because of the magnetic flux is changing, there wake of magnetic flux in the core material. This loss is reduced when used multi-layer core.

Distribution transformers and parts

2011-07-10T20:39:00.000-07:00

The distribution transformer is a very important component in the distribution of electricity from distribution substations to consumers. Damage to the Distribution Transformer cause kontiniutas customer service will be disrupted (occurring power outages or blackouts). Blackout is a loss which causes the generation costs will increase depending on the price of unsold KWH. Selection of Distribution Transformer rating is not in accordance with the needs of the load will cause the efficiency to be small, as well as the placement location of distribution transformers are not suitable influence on the consumer end of the voltage drop or fall / voltage drop in the end of the channel / consumer.

Transformer or transformer is a component of an electromagnet that can transform high voltage to low or vice versa within the same frequency. Transformer is the heart of the distribution and transmission are expected to operate up to (work continuously without stopping). In order to function properly, eating the transformer must be maintained and cared for properly using the system and the right equipment. Transformer can be distinguished by its power, transformer 500/150 kV and 150/70 kV transformer called Interbus Transformer (IBT) and the transformer 150/20 kV and 70/20 kV distribution transformers are called. Transformers are generally grounded at the neutral point according to the need for system security or protection. For example, 150/20 kV transformer is grounded directly in the neutral 150 kV and 70/20 kV transformer is grounded by low resistance or high resistance or directly on the side of the neutral 20 kV.
Distribution transformers and parts

Parts of the distribution transformers are:
Primary winding
Secondary winding
Core

Distribution transformer serves to lower the tension 20kV medium voltage distribution transmission so that the equipment is 220/380V transformer unit (3 phase).

Some Components Distribution Transformer

1. Tertiary coil:

In addition there are several primary and secondary transformer coils are equipped with a third or tertiary winding. It is necessary to obtain tertiary voltage or for other needs.

Tertiary coil is often used also for connecting auxiliary equipment such as condenser Synchrone, shunt capacitors and shunt reactors.

2. Cooling medium:

Transformer oil should qualify them. :

a. insulation resistance (> 10kV/mm)

b. Density should be small

c. Low Viscosity

d. A high flash point, not easily evaporate who may harm

e. Not damage the insulating material at t (sifatkimia 'y)

3. Tap changer (tap changer):

Tap Changer is the change ratio of the transformer to obtain the operating voltage of the desired secondary voltage network / primary changes. The tap changer can be operated either in a state under load (on-load) or in a state unburdened (off load), depending on its type.

Distribution transformers can be mounted outside ruanga (outside installation) and can be fitted the room (fitting in) depending on the state of the load location. Maintenance is one kompanen that directly supports the reliability, power and quality of production capable of an equipment. Maintenance is not just a physical work that directly to the equipment concerned, but we need a good planning and supervision of its implementation, so that maintenance will be done regularly and in accordance with the provisions, directives applicable to the equipment concerned.
Appropriate distribution, rating according to the needs of the load will keep the voltage drop in the consumer and will increase the efficient use of distribution transformers. So the distribution transformer is one of the equipment that needs to be maintained and used as possible (as efficiently as possible), so the reliability / continuity of service to be guaranteed.

electrical transformer and some of its components

2011-07-10T20:10:00.000-07:00

Transformer or power transformer is a device used to convert AC line voltage, transformers made from two coils wrapped around a soft iron ring.

The coil is connected to a voltage source called the primary coil and the coil where the result is called the secondary coil. When the switch is connected, electricity flows through the primary coil and soft iron turn into a magnet.

Galvanometer needle moves a moment and go back to zero. When the switch is disconnected, the electricity stops flowing in primary coil so that the ring lost kemagnetannya, and the galvanometer needle moves back to a moment in the opposite direction.

By changing the direction of electric current continuously, then the magnetic poles will also change continuously

Electricity generated by the coil secondary coil only for a moment because this is only changing the number of lines of magnetic force when power is switched on or when power is turned off.

By connecting the primary coil to the AC power source, the electric currents are always changing, always changing the magnetic poles and coil secondary continuously changing magnetic lines of force and produce power continuously

So that the coil secondary continuously generate electricity, then he should change the magnetic lines of force continually, that is by changing the pole-pole magnets continuously
electrical transformer and some of its components:

1. Iron core
Electrical transformer iron core serves to simplify the way flux, magnetic posed by electric current through the coil. Made of thin steel plates are insulated to reduce heat (as the iron losses) generated by Eddy Current.

2. Transformer coil
Transformer coil is a few winding insulated wire forming a coil or coils. The coil consists of a primary coil and secondary coil are well insulated against the iron core and to the inter-coil with solid insulation such as cardboard, pertinak and others. The coil as a means of transformation of voltages and currents.

3. Transformer Oil
Transformer oil is one of the liquid insulating material used as insulation and coolant in the transformer.
• As part of the insulating material, the oil must have the ability to resist breakdown voltage, whereas
• as a transformer coolant oil should be capable of reducing the heat generated,
so with both the ability of the oil is expected to be able to protect the transformer from the disorder.

Electrical transformer oils have an element or compound contained hydrocarbons are paraffinic hydrocarbon compounds, hydrocarbon compounds naftenik and aromatic hydrocarbon compounds. Besides the three compounds, transformer oils still contain a compound called additives although its content is very small.

The types of equipment maintenance are as follows:
Predictive Maintenance (Conditional Maintenance) is a maintenance yangd ilakukan way to predict the condition of an electric equipment, if and when electrical equipment is likely to fail. With
predict these conditions can be known early symptoms of damage. Commonly used way is to monitor the condition of them online either at the equipment to operate or not operate. This requires equipment and
specialized personnel for analysis. Maintenance is also called maintenance based on condition (Condition Base Maintenance).

Preventive Maintenance (Time Base Maintenance)

maintenance activities are undertaken to prevent damage to the equipment suddenly and to maintain the optimum performance of equipment according to technical age. This activity is performed periodically with reference
to: Instruction Manual of the plant, the existing standards (IEC, CIGRE, etc.) and operating experience in the field. Maintenance is called
also with time-based maintenance (Time Base Maintenance).
Corrective Maintenance

is performed with planned maintenance at certain times when abnormal electrical equipment or the performance
low work function at run time in order to restore the original condition with repairs and improvements
installation. Maintenance is also called curative maintenance, which can be a trouble shooting or replacement of part / section of damaged or poorly functioning conducted with the plan.
Breakdown Maintenance

maintenance is carried out after the damage occurred suddenly that the timing is not certain and its emergencies.
Implementation of maintenance equipment can be divided into two kinds:
1. Maintenance of monitoring and carried out by operators or
patrol officer for an unattended substation (Gito - Without substation
Operators).
2. In the form of cleaning and maintenance measurements made by
maintenance officer.