Kamis, 31 Maret 2011


1. Definition and elements of mass communication

Mass communication is the communication that includes the wider community level, carried out by using the mass media with different communication purposes and to communicate information to a wide audience. In mass communication are essential elements that are related to one another. These elements are:


Communicators is the party that uses mass media to modern telecommunications technology so that in spreading an information can be captured quickly by the public. Communicators in mass communication seeks to disseminate information, understanding, insights and solutions with broad community scattered everywhere and without their presence clearly known. In other words communicators trying to communicate is aimed at people who are relatively more widespread, and anonymous nature heterogeneous, message outsiders in general, reach wide audience simultaneously and are in unison.

Communicator is in a complex organization and uses a large cost to prepare and sends messages. On the other hand communicators also seek to profit from the spread of information. As an example can be seen from a communicator in the mass media, mass media communicators in working in a complex organization and contains an extensive division of labor and use of certain fees in conjunction with the job.

Mass media

In mass communication, media is a tool that can link between sources and receivers that are open, where everyone can see, read and hear. Media in mass communication can be divided into two kinds, namely the print media (eg newspapers and magazines) and electronic media (eg radio and television).

Thus the mass media is a medium of communication and information that make the distribution of mass information and mass-accessible, too. The mass media have a paradigm as an agent of change (vanguard change), that's what the mass media contribute to:

- The mass media play a role as a medium of education is always to educate people so smart and become a developed society.

- The mass media contribute to convey information on the community.

- The mass media play a role as a medium of entertainment. In addition, the mass media is also a cultural institution, the institution became funnel culture.

Information mass

Mass information is intended message or information to the public en masse. Mass communication is a common communication and not personal, the message is not addressed to one person because it is open to the entire community. Messages in current mass communication is fast and fleeting. It is said quickly because the message delivered to the audience receiving relatively short or even immediately. Meanwhile, say briefly because the message communicated is usually made to be consumed immediately and not to be remembered.


Gatekeeper is the selectors of information. As mentioned above that mass communication on the run in a mass media organization, then people who are in those who will selecting organization any information that will be broadcast or not broadcast. They also have authority to expand and restrict the information to be broadcast.


Mass audiences are receiving the information disseminated by the mass media. They consist of listeners or viewers of a public mass media. Mass communication aimed at a wide audience of heterogeneous and anonymous. Is heterogeneous because of the message or the information conveyed is open to the public and not directed to only certain classes in society. While the process is anonymous because the audience members individually are not known or known by communicator.


Feedback in mass communication generally is delayed, it is different from feedback on face-to-face communication that is direct. But with technological developments as the feedback is delayed on mass communication has been abandoned.

2. The function of mass communication in society:

In general, mass communication serves to disseminate information, education level, stimulate economic growth and create excitement in someone's life. But along with the development of communication technology is so fast, especially in the field of broadcasting and audiovisual media, causing the function of the mass media has undergone many changes.

Here are some of functions of mass communication in society:

Oversight function

The mass media is a media that can be used to supervise all activities of society in general. The function of supervision in the form of social control as well as warnings and persuasive activities. Supervision and social control can be done with fatherly preventive activity to prevent the things that are not desirable. For example, news about the dangers of HIV AIDS to people's lives are made through the mass media and targeted at the wider community, then the function preventive for people trapped and no action that could cause HIV disease to AIDS.

While the function of persuasion in an attempt to provide a reward and punishment to the public in accordance with what done. The mass media can give rewards to the community activities that are beneficial to other community members, but if the activities conducted are not beneficial and even detrimental to other social functions in society there will be punishment.

In addition, supervision by the mass media to provide warnings about the threats and dangers that threaten society, for example warning of floods and storms. By warning the public to prevent or at least be able to hide and save themselves.

The function of social learning

The main function of mass communication through mass media is doing guiding and social education to the entire community. The mass media served to give enlightenment to the community in which communication took place. The function of mass communication is done to cover up weaknesses paedagogi function which is carried out through face to face communication, because it is the function paedagogi can only take place exclusively between certain individuals only.

Functions of information delivery

Mass communication that uses mass media, has a function as the process of delivering information to the communities at large. Mass communication allows information from public institutions is delivered to the community extensively in quick time so that the informative function of time achieved in quick and brief.

The function of cultural transformation

Mass communication into the process of cultural transformation is carried out jointly with all components in mass communications, especially those supported by the mass media. Cultural transformation function becomes very important and related to other social functions primarily social function learning, though more on the cultural transformation function tasks as part of a global culture.

The mass media disseminate the results of culture through the exchange of radio programs, television and even through the print media. With the development of technology, it can lead to a culture changes. Because the use of technology will facilitate the convergence of various cultures from the outside. Thus, mass communication plays an important role in the process of cultural transformation.


Designing mass media programs with one goal to entertain the public. They provide entertainment to get attention from the audience as much as possible, so that they can sell this to advertisers and they will benefit. While the entertainment side of society is needed to fill time

leisure and a means for recreation. For example, in the television comedy show will help people to momentarily forget the fatigue and boredom in doing everyday tasks, so that after seeing those impressions will be obtained a fresh mind and relax.

Convincingly (to persuade)

Persuasion can come in the form:

- Strengthening or reinforce attitudes

The media reinforce or create beliefs, attitudes, values ​​and opinions become more powerful. For example, religious people will listen to the messages that match trust and they will become stronger in their faith belief. Because in the delivery of the message contains a value that reinforce their understanding of matters in the belief that they profess, so they will become more confident.

- Change

The media can change attitudes, beliefs or values ​​of a person. For example, impressions on television talk show that explores the theme of the importance of adjusting the diet is good. By looking at the first impressions people will feel attracted and will try to listen and listen to explanations from the experts featured in those impressions. After that obtained explanations will be received and kept in mind in mind, so that will bring a new attitude in terms of adjusting the diet daily.

- Mobilize

Viewed from the perspective of advertisers, the most important function of media is to attract consumers to take action. Media trying invite viewers or readers to buy products with particular brands. Once an attitude is formed or an established pattern of behavior, the media serves to channel and control towards the specific.

Creating a sense of unity

Many people who have not realized that mass communication can make us become a member of a group. In addition, the presence of mass media can be utilized in order to bridge the differences, such as ethnic differences. So with the existence of the mass media can be to foster and strengthen national unity
READ MORE - Communicators

Wave Rectifier

wave rectifier
A rectifier voltage, the diode is used to convert alternating voltage (AC) into DC voltage (DC). Rectifier voltage have 2 kinds, namely: 1. Half-wave rectifier (half-wave rectifier) ​​2. Full wave rectifier (full-wave rectifier) ​​1. Half-wave rectifier (half-wave rectifier) ​​When used as a half-wave rectifier, diode becomeone-way AC voltage.

diode is the active component has channel two (thermionic diodes may have a third channel for heating). Diodes have two active electrodes in which electrical signals can flow, and most of the diodes are used because of its characteristics in one direction. Diodes varikap (Variable Capacitor / condenser variable) is used as voltage controlled capacitors.

unidirectional properties owned most types of diodes are often called unidirectional characteristics. The most common function of the diode is to allow electric current to flow in one direction (called the forward bias condition) and to hold the flow from the opposite direction (called a reverse bias condition). Therefore, the diode can be thought of as an electronic version of the valve in the transmission fluid.

Diodes unidirectional actually does not show a perfect life and death (actually brought forward bias current and clogged in reverse bias), but has the electrical characteristics of voltage-dependent currents not linear complex on the technology used and conditions of use. Several types of diodes also have functions that are not intended for use rectifier.

Diode has two legs, namely the anode and cathode. Diode electrical current can pass only from one direction only, namely from the anode to the cathode-called forward bias position (forward). Instead diode will withstand the current flow or blocking flow from the cathode to the anode, which is called reverse bias (reverse). However, the diode has a reverse bias voltage withstand limited-called break-down voltage. If the voltage is passed then the diode is said to corrupt and should be replaced new.
READ MORE - Wave Rectifier

Rabu, 30 Maret 2011

Practical circuit Relay Driver Using Bipolar Transistor

Practical circuit Relay Driver Using Bipolar Transistor
How to design a practical relay driver circuit using bipolar transistor? Here is a bit of a description that can be used as a guide in designing tips or relay drivers using bipolar transistors.

Relay is a component consisting of an iron core coil which will produce an electromagnet when the coil is energized by electric current. Electromagnet is then interesting contact mechanism that would link the normally-open contacts (NO) and normally open contacts-Closed (NC). Little explains, normally the word here means the relay in a non-active or non-energized, or relay coil is not energized. So normally-open contacts (NO) is a contact while Normal is not connected, and contact-Normally Closed (NC) is a contact while Normal connect.

symbol of the component SPDT relay (Single-Pole Dual-Totem) which means having a contact NO and a NC contact with a COMMON. When the coil is energized, the NC contacts will be connected to COM. If the coil is energized, the contacts will move from NC to NO,so will be connected to COM NO .

symbol of the component DPDT (Dual-Pole Dual-Totem) which has 2 NO contacts, 2 NC contacts with 2 of COMMON. There are also relay with 3-Pole and 3-Totem, but I do not think I need to show the picture, simply SPDT and DPDT which are often used in practice.

Relay Characteristics

Previously need I say that is not discussed in this paper about the AC relay, although there are some common characteristics, but it would be better if the AC relays are discussed in separate papers. God willing, if there is a chance I will discuss later.

Briefly, the characteristics of relays include voltage coil / coil. There is a 5Vdc, 12VDC, 24VDC, 36Vdc, 48Vdc to. If there is DC voltage relays coil besides the information shared via the comments please. Working voltage is the voltage to be supplied to the coil for the relay to work. In addition there is a characteristic ability to relay contacts. Can 3A, 5A, 10A, or more. That is the maximum current that can flow by the relay contacts are in accordance with its characteristics, so it could 3A, 5A, or 10A. Indeed, despite being forced to drain the larger currents are also not directly damaged. But that is not the right practice.

Here are some sample images DC relays are widely available in the market.

Relay driver circuit

Bipolar transistor is a component that works based on the presence or absence of flow in the foot triggers the base. In the relay driver applications, the transistor works as a switch that at the time did not accept the current triggers, then the transistor will be in the position of the cut-off and does not conduct current, Ic = 0. And when the base receives the flow triggers, then the transistor will turn into a state of saturation and delivers current.

The following image is a practical series of relay drivers that are reliable for use in microcontroler projects. Please listen carefully
Active component in the above series is 2 pieces of NPN transistors arranged in Darlington. Transistor serves as an electronic switch that will drain current if there is bias currents at the foot of its base, and would clog the flow of current if there is no bias on its base leg. Relay that can be used with this circuit is relay with coil voltage between 5Vdc to 45Vdc. If the relay is used above require working voltage 45Vdc, then replace the transistor C828 with transistors that have a greater work stress such as BD139, for example.

For small relays with a voltage of 5V - 24V, to further save costs, TIP31C transistor can be replaced by a C828 or similar NPN. For large relays, the transistor TIP31C is more than enough to activate the relay with a steady.

Here are a few examples of practical calculations (rather than theoretical, such as when a school or college) in the design of the relay driver circuit using a Darlington transistor.

First do the relay coil resistance measurement. For example here I use a SPDT relay 12V with a current capacity of 5A. From the measurement results of the relay coil resistance value amounted to 358 ohms (you probably will get a different value.) Thus, current is drawn at 12V / 358 ohms = 33.5 mA. So that the transistor should be able to generate currents at least 2-3 times larger than 33.5 mA, which is about 100 mA (in this example I use a multiplier factor of 3).

The transistor used was 2 pieces of type C828 NPN transistors are cheap and easily found in the market. Transistor C828 has a strengthening of the DC current (HFE) of approximately 130-520 times depending on the type of group transistor.Tapi than confused, we consider only the strengthening of the current is equal to 100 times. Transistor C828 has a VBE = 0.8 V.

Darlington transistors arranged so that the strengthening of the current is now 100 x 100 = 10,000 times. Furthermore, a minimum base current can be calculated by: Ib = 100 / 10000 = ± 10 Ua. If the VBE is worth 0.8 volts and the output voltage microcontroller logic 1 value 4.8 volts, then RB can be calculated as follows: RB = (4.8 to 0.8 - 0.8) / 10E-6 = 320000 ohms.

In the circuit used in RB with size of 100 kilo ohms, so the value is Ib = Ib (4.8 to 0.8 - 0.8) / 100000 = 32 UA. Installation of 1N4002 diode prevents transient currents generated by the relay coil.

Tips For AT89S51/52/53/8252 and AVR Microcontroller

The series of relay drivers above are very practical and proven success in various series of controls that had been my design. If used on the AVR microcontroller, the circuit will work very well without any problems, because at the time of the RESET, all I / O ports AVR is at the high-impedance state.

Unlike the case when used in microcontroller AT89S. At RESET, all I / O ports of MCS-51 located on the High logic 1, so long as RESET, the relay will be active for a while. To that end, the program must set the initialization of I / O ports that are used to trigger the relay to the state Low. Another solution is to use a better driver is active-low relay.

Another solution if you drive many relay applications, the ICs can be used ULN2003A, which has 7 pieces ready Darlington transistors used to drive relays.

For information, a series of drivers on I used to drive contactors 48Vdc with current capacity of 200A at the application controller electric forklifts.

So in the above series is suitable for use on applications using the microcontroller because the current source port I / O microcontroller typically only 20mA only.
READ MORE - Practical circuit Relay Driver Using Bipolar Transistor

Working Principle of synchronous generator

Working Principle of synchronous generator

After we discuss here about the construction of a synchronous generator, then this article will discuss about the working principle of a synchronous generator. That would be a framework discussion this time is the operation of synchronous generators in load conditions, no load, determining the reactance and resistance by performing experiments without load (zero load), short circuit experiment and experiment anchor resistance.

As noted in previous articles, that the rotor speed and frequency of the voltage generated by a linear synchronous generator. Figure 1 will show the working principle of an AC generator with two poles, and let us assume only one winding is made ​​of two conductive in series, the Conductor of a and a '.

To be able to more easily understand, please refer to the animation generator working principle, here.
Figure 1. Generator Diagram Pole AC One phase two.

Winding as mentioned above is called "Circumference centered", the generator is actually composed of many loops in each phase are distributed in each of the stator groove and is called "Circumference distributed. " It is assumed rotor rotates clockwise, the rotor flux field moves according coil anchor. One lap in one second rotor produces one cycle per second or 1 Hertz (Hz).

If speed is 60 Revolution per minute (rpm), the frequency of 1 Hz. So for the frequency f = 60 Hz, the rotor should spin 3600 rpm. For the rotor speed n rpm, the rotor must rotate at a speed of n/60 revolution per second (rps). When the rotor has more than 1 pair of poles, for example P poles, each revolution of the rotor induces P / 2 cycle of voltage in the stator winding. The frequency of induced voltage as a function of rotor speed, and formulated by:
For three-phase synchronous generator, there should be three windings, each separated by 120 electrical degrees in space around the circumference of the air gap as shown in the coils of a - a ', b - b' and c - c 'in Figure 2. Each coil will produce a sine wave Flux different from one another 120 degrees electrical. In a balanced state of flux magnitude for a moment:

ΦA = Φm. Sin ωt
ΦB = Φm. Sin (ωt - 120 °)
ΦC = Φm. Sin (ωt - 240 °)
Figure 2. AC Generator Diagram Pole Three Phase Two

The amount of resultant flux is the sum of the three flux vectors are:
ΦT = ΦA + ΦB + ΦC, which is a function where (Φ) and time (t), then the large-magnitude total flux is:
ΦT = Φm.Sin ωt + Φm.Sin (ωt - 120 °) + Φm. Sin (ωt-240 °). Cos (φ - 240 °)

By using trigonometric transformations of the following:

Sin α. Cos β = ½. Sin (α + β) + ½ Sin (α + β),

then from the above equation is obtained:

ΦT = ½. Φm. Sin (ωt + φ) + ½. Φm. Sin (ωt - φ) + ½. Φm. Sin (ωt + φ - 240 °) + ½. Φm. Sin (ωt - φ) + ½. Φm. Sin (ωt + φ - 480 °)

From the equation above, when described the ethnic unity, third, and fifth
will eliminate cross. Thus from the equation will be obtained
total flux, ΦT = ¾ Φm. Sin (ωt - Φ) Weber.

So the resultant field is a rotating field with modulus 3 / 2 Φ with
turning angle of ω. So the voltage of each phase are:

E max = Bm. ℓ. ω r Volt


Bm = maximum flux density of rotor field coil (Tesla)
ℓ = length of each coil in a magnetic field (Weber)
ω = angular velocity of rotor (rad / s)
r = Radius of the anchor (meters)

you can also read articles related to the discussion this time, at:

- Electromechanical in power systems-1, here.
- Electromechanical in power systems-2, here.

Generator Without Charges

If a synchronous machine functioned as a generator to be played at synchronous speed and rotor given field current (IF), then at anchor stator coil will be induced no-load voltage (Eo), which is:

Eo = 4.44. Kd. Kp. f. φm. T Volt

In the state of no-load current does not flow in the stator yoke, so there is no influence of the anchor reaction. Flux is only generated by the field current (IF). When the field current is increased, then the output voltage will also rise to the point of saturation (saturated), as shown in Figure 3. Generator no-load conditions can be described equivalent circuit as shown in Figure 3b.
Figure 3a and 3b. Curves and Equivalent Series Generator Without Charges

Generator load

When the generator load implies changing the size of the terminal voltage V will vary also, this is due to the loss of stress:
• Resistance of anchors Ra
• Reactance Xl leak anchor
• Anchor Xa Reaction

a. Resistance Anchor
Anchor resistance / phase Ra cause of the loss tense / phase (voltage fall / phase) and I. Ra which anchors the current phase with the grid.

b. Leaks reactance Anchors
When current flows through conductive anchor, some things did not induce flux in the path that has been determined, it is called Flux Leaks.

c. Reaction Anchor
The existence of current flowing in the coil when the generator loaded anchor would cause flux anchor (ΦA) which integrate with the flux generated in the rotor field coil (ΦF), so it will produce a resultant flux of:
The interaction between these two fluxes is referred as a reaction anchor, as shown in Figure 4. which illustrates the anchor reaction conditions for this kind of different loads.

Figure 4a, 4b, 4c and 4d. Reaction conditions Anchors.

Figure 4a, shows the reaction conditions when the generator loaded anchor resistance (resistive) so that the current phase with the grid emf He anchors Eb and ΦA be perpendicular to the ΦF.

Figure 4b, shows the reaction conditions when the generator loaded anchor capacitive, so the current anchor, he goes before emf Eb of θ and ΦA ΦF backward toward the corner (90-θ).

Figure 4c, shows the reaction conditions the anchor when loaded, resulting pure capacitive currents precede emf Eb He anchors at 90 ° and ΦA will strengthen that influence ΦF magnets.

Figure 4d, shows the reaction conditions when the current anchors are pure inductive load currents resulting anchor of emf Eb He was retarded by 90 ° and would weaken ΦF ΦA that affect magnets.

The amount of leakage reactance reactance XL and the anchor Xa called Synchronous reactance Xs.

Vector diagram for the load that is inductive, purely resistive, and capacitive shown in Figure 5a, 5b and 5c.

The interaction between these two fluxes is referred as a reaction anchor, as shown in Figure 4. which illustrates the anchor reaction conditions for this kind of different loads.
Figure 5a, 5b and 5c. Vector Diagram of Generator Expenses

Based on the picture above, it can determine its voltage falls that occur, namely:

Total Voltage Fall on Charges:

= I. Ra + j (Xa + I. I. XL)
= I {Ra + j (Xs + XL)}

= I {Ra + j (Xs)}

= I. Zs

Determining the Resistance and Reactance

To be able to determine the value of reactance and impedance of a generator, should be carried out experiments (test). There are three types of tests commonly performed, namely:

• Test without load (Zero Cost)
• Short circuit test.
• Resistance Anchor Test.

Test Without Charges

Test Without Charges made ​​on the speed of Sync with the anchor chain is open (no load) as shown in Figure 6. Experiments carried out by regulating the field current (IF) from zero to rated voltage output terminal is reached.

Figure 6. Generator Test series without expense.

Short circuit Test

To perform this test generator terminal short-circuited, and with Ampermeter placed between two conductive which is short circuited (Figure 7). Field current increased gradually until the maximum available current anchor. During the test process of the If current and short circuit current IHS recorded.
Figure 7. Generator Test series in short circuit.

From the results of the two tests above, it can be drawn in the form of characteristic curves as shown in Figure 8.
Figure 8. Characteristic Curves Without Charges and short circuit of a generator.

Sync Impedance searched based on test results, are:
If = constant

Resistance Anchor Test

With a series of open terrain, the DC resistance measured between two output terminals so that the two phases connected in series, Figure 9. Resistance per phase is half of that measured.
Figure 9. DC Resistance Measurement

In fact, the resistance value multiplied by a factor to determine the effective value of AC resistance, R eff. This factor depends on the shape and size of the plot, Conductor size anchors, and coil construction. Its value ranges between 1.2 s / d 1.6.

If the value of Ra is well known, the value of Xs can be determined based on the equation:
READ MORE - Working Principle of synchronous generator

Electric motor

Electric motor
In the article "The classification of electrical machinery, electric motors including into the category of dynamic electric machine and it is an electromagnetic device that converts electrical energy into mechanical energy. Mechanical energy is used for, for example, rotating impeller pump, fan or blower, compressor moving, lifting materials, etc. in the industry and is also used in household electrical appliances (such as: mixers, electric drill, electric fan).

You can see an animation of this DC motor working principle here.

The electric motor is sometimes called the "work horse" of his industry, because it is estimated that motors use about 70% of the total electrical load in the industry.

Mechanism of action for all types of electric motors are generally similar (Figure 1), namely:
• An electric current in a magnetic field will exert a force.
• If the wire that carries the flow is bent into a circle / loop, then both sides of the loop, ie at right angles to the magnetic field, will gain force in the opposite direction.
• Couple style produces power play / torque to rotate the coil.
• motors have several loops on dynamo to provide a more uniform torque and the magnetic field generated by the electromagnetic structure of the so-called field coils.

In understanding an electric motor, it is important to understand what is meant by the motor load. Expense refers to the output power play / torque in accordance with the required speed. Expenses can generally be categorized into three groups:
• constant torque load, is the burden which the demand for its energy output varies with the speed of operation, but its torque does not vary. Examples of constant torque loads are conveyors, rotary kilns, and the constant displacement pump.
• Expenses with variable torque, is the load torque that varies with the speed of operation. Examples of variable torque loads are centrifugal pumps and fans (torque varies as the square of velocity).
• Expenses with constant energy, is the load torque change with demand and inversely proportional to speed. Examples for the constant power load is machine tools.
Figure 1. Working Principles of Electric Motors.


This section describes the two main types of electric motors: DC motors and AC motors. Motorcycles are classified based on the input supply, construction, and operation mechanism, and further described in the chart below.
Figure 2. Classification of Electric Motors.

1. Motor DC / Direct Current
Motor DC / DC current, as the name implies, uses direct current indirect / direct-unidirectional. DC motors are used in special applications where high torque is required ignition or acceleration is fixed for a broad range of speed.
Figure 3 shows a DC motor which has three main components:
• Pole field. In simlpe illustrated that the interaction of two magnetic poles will cause the rotation of the DC motor. DC motor has a stationary field poles and armature that moves bearing on the space between the polar terrain. Simple DC motor has two field poles: north pole and south pole. Lines of magnetic energy through the enlarged openings between the poles from north to south. For larger motors or more complex consists of one or more electromagnets. Electromagnet to receive electricity from outside resources as a provider of field structure.
• Dynamo. When the flow goes through the armature, then this flow will be an electromagnet. A cylindrical armature, connected to the countershaft to drive the load. For the case of a small DC motor, the armature rotates in a magnetic field formed by the poles, to the north and south magnetic poles switch location. If this happens, the current is turned to change the poles of north and south of the dynamo.
• commutator. This component is mainly found in DC motors. Usefulness is to reverse the direction of electric current in the armature. commutator also assist in the transmission of current between the armature and resources.
Figure 3. DC motor.

The main advantage is the speed of DC motor easily controlled and does not affect the quality of power supply. This DC motor can be controlled by adjusting:
• dynamo voltage - increasing the armature voltage will increase the speed.
• Flow field - reducing the field current will increase the speed.

DC motors are available in many sizes, but their use is generally restricted to some use of low-speed, low power usage to moderate, such as machine tools and rolling mills, because often there are problems with mechanical electric current changes direction at a larger size. Also, the motor is restricted only for use in the area is clean and not dangerous because the risk of sparks at the brush. DC motors are also relatively expensive compared to AC motors.

The relationship between speed, field flux and armature voltage is shown in the following equation:

Electromagnetic force: E = KΦN

Torque: T = KΦIa

E = electromagnetic force developed at the armature terminals (volts)
Φ = flux field which is proportional to the flow field
N = speed in RPM (revolutions per minute)
T = electromagnetic torque
He = armature current
K = constant equation

Types of DC motors / direct current

a. DC motors separate power source / Separately Excited, If the field current supplied from a separate source of DC motors it is called a separate power source / separately excited.

b. DC motor own resources / Self Excited: shunt motor. In the shunt motor, the field winding (shunt field) are connected in parallel with the armature coil (A) as shown in Figure 4. Therefore the total current in the path is the sum of field current and armature current.
Figure 4. Characteristics of DC Shunt Motor.

Following the shunt motor speed (ETE, 1997):
• The speed is practically constant independent of the load (up to a certain torque when the speed is reduced, see Figure 4) and is therefore suitable for commercial use with low initial load, such as machine tools.
• Speed ​​can be controlled by placing a detainee in the composition series with the armature (reduced speed) or by putting detainees in the flow field (velocity increases).

c. DC motor power alone: motor series. In a series motor, the field winding (shunt field) is connected in series with the armature coil (A) as shown in Figure 5. Therefore, the flow field with armature current.

Following on the series motor speed (Rodwell International Corporation, 1997; LM Photonics Ltd, 2002):
• Speed ​​limited to 5000 RPM.
• Must avoid running series motor with no load because the motor will accelerate uncontrollably.
Series motors are suitable for use requiring high starting torque, such as crane and hoist lifting equipment (see Figure 5).
Figure 5. Characteristics of DC Motor Series.

d. DC Motor Compound / Combined.
DC compound motor is a combination of series and shunt motors. In the compound motor, the field winding (shunt field) is connected in parallel and in series with the armature coil (A) as shown in Figure 6. Thus, compound motors have excellent starting torque and stable speeds. The higher the percentage of incorporation (ie the percentage of the field winding is connected in series), the higher the starting torque can be handled by this motor. For example, incorporation of 40-50% makes this bike suitable for hoist and crane lifting equipment, whereas the standard compound motor (12%) did not match (myElectrical, 2005).
Figure 6. Compound DC Motor Characteristics.

2. Motor AC / Alternating Current Behind

Motor AC / alternating current using an electric current that reverses its direction at regular intervals. AC electric motor has two basic parts power: "stator" and "rotor" as shown in Figure 7.

The stator is a component of static electricity. The rotor is rotating electrical components to rotate the motor shafts. The main advantage of AC motors, DC motors is that the speed of AC motor is more difficult to control. To overcome this disadvantage, AC motors can be equipped with variable frequency drive to increase speed while lowering power control. Induction motors are the most popular motorcycle industry because of their reliability and easier maintenance. AC induction motor is quite cheap (the price is half or less than the price of a DC motor) and also provides power to weight ratio is quite high (about twice a DC motor).

Types of Motor AC / Alternating Current Behind

a. Synchronous motor. AC synchronous motor is a motor that works on fixed speed at a certain frequency system. This motor requires direct current (DC) for power generation and has a low starting torque, and therefore synchronous motor suitable for use beginning with low load, such as air compressors, generators and motor frequency changes. Synchronous motor is able to improve system power factor, so often used in systems that use a lot of electricity.

The main component is a synchronous motor (Figure 7):
• Rotor. The main difference between synchronous motors with induction motors is that the rotor synchronous machines running at the same speed with the rotation of the magnetic field. This is possible because the rotor magnetic field is no longer induced. The rotor has permanent magnets or DC-excited, which was forced to lock in a certain position when confronted with another magnetic field.
• Stator. The stator produces a rotating magnetic field is proportional to the supply frequency.

This motor rotates at synchronous speed, which is given by the following equation (Parekh, 2003):

Ns = 120 f / P

f = frequency of the supply frequency
P = number of poles
Figure 7. Motor Sync.

b. Induction motor. Induction motors are the most common motor used in various industrial equipment. Its popularity because of its design is simple, cheap and easily available, and can be directly connected to AC power source.

Components of Induction motors have two main electrical components (Figure 8):
• Rotor. Induction motor using two types of rotor:
- Squirrel cage rotor consists of thick conductive rod that is attached in patches of parallel slots. Rods are given a short circuit at both ends by means of a short circuit ring.
- The circle rotor which has a roll of three-phase, double layer and distributed. Created by circular stator poles. Three phases heavily wire on the inside and the other end is connected to a small ring that is placed on the rod as with a brush attached to it.
• Stator. The stator is made from a number of stampings with slots to carry three-phase coils. The roll is looped for a certain number of poles. The roll was given a space geometry of 120 degrees.

Classification of induction motor

Induction motors can be classified into two main groups (Parekh, 2003):
• single-phase induction motors. This motor has only one stator winding, operates with single-phase power supply, having a squirrel cage rotor, and requires an appliance to turn on the bike. So far this bike is the most common types of motors used in household appliances such as fans, washing machines and clothes dryers, and to use up to 3 to 4 hp.
• three-phase induction motors. A rotating magnetic field generated by a balanced three-phase supply. The motor has high power capability, can have a squirrel cage rotor or coil (although 90% had a squirrel cage rotor), and ignition of its own. It is estimated that approximately 70% of motors in industrial use of this type, for example, pumps, compressors, conveyor belts, electrical networks, and grinder. Available in sizes 1 / 3 to hundreds of hp.
Figure 8. Induction Motor

Induction motor works as follows, Electricity is supplied to the stator that will generate a magnetic field. This magnetic field moving at a speed synchronous around the rotor. Rotor currents produce a second magnetic field, which is trying to fight the stator magnetic field, which causes the rotor to spin. However, in practice, the motor never worked at synchronous speed but in the "basic rate" is lower. The occurrence of differences between the two speeds are caused by "slip / slide" which increases with increasing load. Slip only occurred on induction motors. To avoid the slip rings can be mounted a sliding / slip rings, and the motor is called "motor ring shear / slip ring motor. "

The following equation can be used to calculate the percentage of slip / slide (Parekh, 2003):

% Slip = (Ns - Nb) / Ns x 100

Ns = synchronous speed in RPM
Nb = base speed in RPM

The relationship between load, speed and torque
Figure 9. Graph of Induction Motor Torque vs. Speed

Figure 9 shows the graph of torque vs. speed three-phase AC induction motor with a predefined flow. When the motor (Parekh, 2003):
• Start burning flame turns out there is an initial high current and low torque ("pull-up torque").
• Achieve 80% full speed, torque is at its highest level ("pull-out torque") and the flow began to fall.
• At full speed, or synchronous speed, torque and stator currents down to zero.
READ MORE - Electric motor

ATM (Automatic teller machine or automated teller machine, in Indonesia also sometimes stands for automatic teller machines)

ATM (Automatic teller machine or automated teller machine, in Indonesia also sometimes stands for automatic teller machines) is an electronic tool that allows bank customers to take the money and checking their savings accounts without the need to be served by a "teller" man. Many ATMs also allow storage of cash or checks, transfer money or even buy stamps.

In everyday life we ​​are already familiar with the name of the ATM (Automatic Teller Machine), either through hearing or sight. For people who live in urban and rural areas are already familiar with ATM vocabulary. With rapid technological developments currently any transaction can be done through ATMs, ranging from cash withdrawal, transfer, handling the books, bill payments, cash deposits or even printed books can be done at the ATM.

An ATM card as the media need an intermediary between man and machine. On a card has a line called Magnetic Chip. Magnetic Chip has the function as a sensor detecting the identity of the owner. Magnetic Chip is very sensitive to various circumstances, for example when rubbed by a Magnetic Chip Magnetic Chip object then it has lost its function. Because if there is friction on the Magnetic Chip ATM machines can not detect the ATM card owned by a customer. Something like that is a weakness of the transaction through the ATM. This happens because of negligence of the customer so that the card in this case is damaged. How to renew it? Customers can directly consult with the concerned bank. The weakness of the engine itself is usually derived from its network. If there is damage to his ATM machine is usually the operator of the bank concerned will immediately fix it.

In Indonesia, we also know there is the term ATM Bersama, if given the understanding of the ATM Bersama is a merger or cooperation of several banks in terms of customer service using the ATM interface of the media, here from an ATM machine to serve customers to conduct transactions from various banks by using computerized systems and telecommunications. Computerization and telecommunication systems are not only used for the ATM shared but are also used for ATM Mandiri. As has been learned Praise be to Allaah technology that support for information systems leads to the timeliness needed a system that mutually support each other.

On the technology Automatic Teller Machine (ATM) using computerized systems and telecommunications that meet the standards of a component information input system. An input device must have a way of working, on the ATM itself has work orders from customers to the bank operator. Transmitter in the ATM transmitter located in the bank using a system using a system Telecommunications Telecommunications. Relationship occurs between the ATM with the bank using Telecommunications system.

Know more ATMs in, what the heck component is in the ATM so as to serve various kinds of transactions, it could be for those of you who still lay in the ATM may be that there are people who sit down if there is a calculated money grab first after it removed then given evidence of withdrawal. Actually ATM component that consists of ATM box, the number keys, the screen and camera (optional) is commonly visible from the outside, while inside bsia consists of one unit of computer CPU, key board, modem, city money, small printer and card reader.

ATM Components

Every transaction that happens the information will be received by the computer and then sent to the data center through a telecommunication facility could line telephone, and radio Vsat, ATM can be monitored status of the data center that can be known whether this ATM is dead or his money was gone.

ATM machine consists of 2 parts:
a. Upper (Upper Compartement):
- Monitor
- Customer keypad
- Card reader
- Journal printer
- Receipt Printer

b. Bottom (Lower Compartement):
- Combination lock
- Dispenser module
- Cash cassette
- Reject cassette

USE OF ATM (Automatic Teller Machine)

A. In the World
With the ATM is to make our lives easier, because the current ATM network can already cross-country and even across continents for example, you can withdraw cash transactions in any country if you hold a picture of Master card Cirrus Maestro, you can get cash at ATMs Maestro Cirrus logo is there, as well as your Visa card with a picture of Visa Electron, you can take the money in the existing ATM Visa Electron logo. ATM usage in developed countries has been very good so that the average per day can reach 500 - 1000 transaction per day.

B. In Indonesia
Although ATM has been very popular in Indonesia, almost everyone is familiar with and hear the words of the ATM but the extent of its use is still not optimal for the size of a large bank with an extensive network such as the BCA, the financial transactions of about 800 thousand transactions per day, from about 2500 ATMs so average transaction at the ATM is only about 320 transactions per day, this amount is actually not optimal when compared with investment costs incurred. For the average usage per day ATMs throughout Indonesia for all banks is still less than 300 transactions per day.


ATM is a data terminal device that has two input and four output devices. Just as a data terminal, ATM must have a connection, connect, and communicate through a host processor (central processing). Central process that is accompanied by an Internet service provider (ISP) that serves as a gateway route to get to control every aspect of ATM network and make the kinds of functions for the ATM card holders (people who want money.)

In general, the central processes that support can be via Leased-line or line of contract (lease) or dial-up machine (telephone). Leased-line machines connect directly to the central process through the four-wire (four-wire), point-to-point, dedicated telephone line (telephone line option). Dial-up ATMs connect to a central process through a normal telephone line using a modem and connection toll free number, or through Internet service providers who use local access numbers. Leased-line ATMs recommended for use in a solid location for thru-put capability job market is relatively heavy, and dial-up ATMs recommended for use in stores or locations that are not crowded where the use of just taking money. The cost required for a dial-up ATM machine is less than half leased-line ATM machines. Operating cost dial-up ATM machine is also only a fraction of the cost of operating leased-line ATM machines.

The central processing may be owned by a bank or financial institution, or may also owned by internet service providers who stands alone. If you owned a bank, usually only support a bank ATM machine itself, where only a single process that is available to owners of shops or business premises.

Financial Transactions

At the time the card holder wants to do an ATM transaction, the person must provide the information needed by the detector card and keypad are available. ATM machines will forward this information to the central process, through data communications channels that have been appointed to conduct the transaction request to the bank in accordance with a user card. If the cardholder wants cash withdrawal, the center of the process will charge transfer (electronic funds transfer) to replace the central bank service fee from the customer-owned bank. At the time the cost has been transmitted to the central bank, then the processor will send the code approval (approval code) to the ATM as the machine authorization to issue cash. Then the processor will send data of financial transactions to the cardholder's home bank ATM users, usually the next business day. In this case, the Bank is home to replace the entire cost of the ATM machine.

Independent ATM can access a variety of banks, also supports the placement of the number of ATMs that a lot with various brands of commerce (Merchant). So, when you do a cash transaction, money is flowing electronically from your account to your service provider and trademarks are used.


Magnetic strip is a short form of plastic which is coated with a magnetic system and is usually attached to credit cards or other valuable cards. On the magnetic strip is usually written cardholder personal data, which contains the account number, personal as well as its access code. And this paper was written in the form of certain codes, and can only be read by a computer equipped with special machinery for magnetic strip cards.

Money machine that is used to read cards with magnetic-strip plastic is then known as ATM (Automated Teller Machine). To use it, the user must insert the card into a machine owned by a special or an ATM machine and enter the code number, and the amount of money that will be taken. No password is then sent through the telephone network central kekomputer. Computers will see, whether concerned with money deposits or not.

If you have, then this signal is sent again to-ATM and to then, ATM will disburse a sum of money in accordance with the needs required. In addition, users can also see information on its balance of savings, current account or deposit it. The transfer of the books will automatically be done by computer. In an ATM (Automated Teller Machine) also contained a satellite that will transmit information in computer center.

ATM system consists of:
1. Workstations that can be accessed with a special card or collectively, the ATM machine
2. Remote computers that store and update customer records and authorize and execute transactions
3. Telecommunication relationship between the ATM machine with a remote computer.
READ MORE - ATM (Automatic teller machine or automated teller machine, in Indonesia also sometimes stands for automatic teller machines)

Audio power amplifier (power amplifier)

Performance of the prototype
Output power (RMS ):… 140W into 8 ohms, 200W into 4 ohms
Frequency Response:. 20Hz – 80kHz-1dB points (see Figure 1)
Input sensitivity: ………… 830mV for 200W into 4 ohms
Distortion: … <0.1% (20 Hz – 20 kHz) (see Fig.2) Signal-to-Noise Ratio:. > 102dB unweighted, 105dB A-weighted with respect to 200W into 4 ohms.

Audio power amplifier (power amplifier) ​​is an electronic plane that serves to strengthen the voice signal that can be derived from a radio, tape recorder, cd player, preamp mic or the other. Audio power amplifier OCL system load with power amplifier connected directly (direct copel) without using capacitors and transformers. Application of OP Amp 741 IC is used as a booster ahead of the audio amplifier circuit to replace the transistor as an amplifier front.

The problem of this research is how the performance of audio power amplifier OCL system by applying OP Amp IC 741 as the amplifier front. The purpose of this study was to investigate the characteristics of an audio amplifier OCL system by applying the Op Amp IC 741 as an amplifier ahead and realize the audio amplifier OCL system by applying the Op Amp IC 741 as the amplifier front. The benefits of this research is for researchers to apply the theories that have been obtained while for the reader is to provide reference and add to the treasury the power amplifier circuit audio field.

The results of this study was to realization of an audio power amplifier OCL system by applying OP Amp IC 741 as the amplifier front. In the measurement, audio power amplifier has a strengthening registration 13.33 times or a total of 22.49 dB at a frequency of 5 Hz and 10 Hz. Strengthening increased to 18.89 times, or 25.52 dB at a frequency of 15 Hz. At a frequency of 20 Hz to 20 KHz has strengthened 24.44 times or 27.76 dB. On the frequency of 25 KHz to 35 KHz strengthening fell to 23.89 times, or 27.56 dB. While on a theoretical calculation is 26.45 times the amount of reinforcement. There is a difference in the strengthening of 2.01 times. Magnitude percent error of measurement is 8.22%. Differences between measurements and calculations that occur due to several things, among others: the calculation of unknown obstacles contained in the circuit path, whereas in reality a series of lines on the PCB also has a value of resistance other than that there are constraints on the instruments will also affect the results of measurements . The quality of the components and the quality of measuring instruments used also affects the measurement results obtained. The most important characteristic of the audio amplifier is the frequency response, expressed by a graph of frequency response. Based on research data indicated an audio power amplifier with good characteristics, namely the audio frequency (20 Hz - 20,000 Hz) has a reinforcement of the same or equal.

Suggestions from this study, an audio power amplifier OCL system by applying the Op Amp IC 741 as an amplifier of this front with further research can be used as a reinforcement tool other instrumentation. It is recommended to install the heatsinks are sufficient in 3055 and 2955 TIP transistors for the transistor is not easily damaged, because the heat generated is large enough.
READ MORE - Audio power amplifier (power amplifier)

Senin, 28 Maret 2011

A microcontroller (MCU) is a small computer in a single integrated circuit consisting of a CPU is relatively simple combined with support functions su

A microcontroller (MCU) is a small computer in a single integrated circuit consisting of a CPU is relatively simple combined with support functions such as crystal oscillators, timers, sensors, serial and analog I / O etc.
Program in the form of NOR flash memory or ROM OTP also often included on the chip, and, usually small, the R / W memory.
Microcontroller designed for small applications. Thus, in contrast to microprocessors used in personal computers and high performance applications, simplicity is emphasized.
Some microcontrollers can operate at clock frequencies as low as 32KHz, because it sufficient for some applications, and enables low power consumption (miliwatt or microwatts).
Microcontroller has the ability to maintain function while waiting for an interrupt; power consumption when idle (CPU clock and peripherals most off) may only nanowatts, so much of a microcontroller suitable for certain applications with battery / power supply that is more durable.
Microcontroller is used for the production of devices with the performance of automatic and controlled according to the function and logic, such as automobile engine control systems, remote controls, office machines, equipment, electrical equipment, and toys. By reducing the dimensions and size of the device then the costs can be reduced compared with a design that uses a separate microprocessor, memory, and input / output devices, microcontroller makes the process of making a digital devices become more economical.

Microcontroller AT89S51 type is MCS-51 microcontroller family with the exact same configuration with a fairly famous AT89C51, AT89S51 has a feature only ISP (In-System Programmable Flash Memory). This feature allows the microcontroller can be programmed directly in an electronic system without going through the Board or Downloader Programmer Board. Microcontroller can be programmed directly through a cable ISP that is connected to the parallel port on a Personal Computer.
The features of the microcontroller AT89S51 is as follows:

1. A CPU (Central Processing Unit) 8 bits which include MCS51 family.
2. Internal oscillator and timing circuit, 128 bytes of internal RAM (on chip).
3. Four programmable I / O ports, each consisting of an 8-lane I / O
4. Two 16-bit Timer Counter.
5. Five of the interrupt lines (2 and 3 external interrupt internal interruptions)
6. A serial port with full duplex UART serial control.
7. The ability to execute multiplication, division and Boolean operations (bit)
8. The speed of execution of instructions per cycle 1 microseconds at 12 MHz clock frequency
9. 4 Kbytes Flash ROM that can be charged and removed up to 1000 times
10. In-System Programmable Flash Memory

With the above features, making use AT89S51 devices become more simple and does not require a lot of support ICs. So the microcontroller AT89S51 has a privilege in terms of hardware. The block diagram of the microcontroller 89S51.
Block diagram of the microcontroller 89S51
AT89S51 Microcontroller Pin Configuration
The composition of pin microcontroller AT89S51
Pin Configuration AT89S51
Microcontroller AT89S51 has a pin numbered 40 and is generally packaged in a DIP (Dual Inline Package). Each pin on the microcontroller AT89S51 has a purpose as follows:
Port 0
Port 0 is port two functions that are on pins 32-39 of the AT89S51. In a simple system design this port as the port I / O versatile. For a more complex design involving an external memory of this track dimultiplek to the data bus and address bus.
Port 1
Port 1 is reserved as I / O ports and are on pins 1-8. Some of the pins on this port has a specific function of P1.5 (motion), P1.6 (MISO), P1.7 (SCK) is used to track download the program.
Port 2
Port 2 (pins 21-28) are two functions of the port as I / O versatile, or as high byte address bus for external memory involving design.
Port 3
Port 3 is a port of the two functions that are on pins 10-17, the port has multiple functions, such as those found in table 1.1 below:

B0h P3.0 RXD Receive data for serial port
B1h P3.1 TXD Transmit data for serial port
P3.2 INT0 External interrupt 0 B2h
P3.3 INT1 External interrupt 1 B3h
B4h P3.4 T0 Timer / counter 0 external input
B5h P3.5 T1 Timer / counter 1 external input
P3.6 WR B6h External data memory write strobe
P3.7 RD B7h External data memory read strobe

PSEN (Program Store Enable)

is an output signal is found on pin 29. Its function is as a control signal to allow the microcontroller to read the program (code) from external memory. Normally this pin is connected to pin EPROM. If the execution of the program from the internal ROM or from flash memory (Atmel AT89SXX), it is in the inactive state (high).

ALE (Address Latch Enable)
ALE output signal on pin 30 which is the same function with ALE on microprocessor INTEL 8085, 8088 or 8086. Demultiplek ALE signal is used for bus address and data bus. ALE signals generate pulses of 1 / 6 the oscillator frequency and can be used as a clock that can be used in general.

EA (External Access)
There is signal input on pin 31 which can be logic low (ground) or logic high (+5 V). If given the logic high then the microcontroller will access the program from an internal ROM (EPROM / flash memory). If given a logic low, the microcontroller will access the program from external memory.

RST (Reset)
Input reset on pin 9 is the master reset for AT89S51. Pulse transition from high to low for 2 cycles will reset the microcontroller.

Provided on-chip oscillator driven by XTAL is connected to pin 18 and pin 19. Necessary stabilizing capacitor of 30 pF. Great XTAL value of about 3 MHz to 33 MHz. XTAL1 is the input to the reversal of the oscillator amplifier (inverting oscillator amplifier) ​​and an internal clock input to the operation of the circuit. While XTAL2 is the output of oscillator amplifier reversal.

XTAL Oscillator Configuration
AT89S51 operated at supply voltage of +5 v, pin Vcc is at number 40 and VSS (ground) on pin 20.

Memory Organization
a. Separation of Program and Data Memory
All 8051 devices have separate address spaces for program memory and data memory, as shown in gambar1.1. and figure 1.2. The logical separation of program memory and data memory allows data to be accessed by 8 bits, which can be quickly stored and manipulated with an 8-bit CPU. In addition, 16-bit data memory addresses can also be raised through the DPTR register. Program memory (ROM, EPROM) can only be read, not written. Program memory can reach up to 64K bytes. At 89S51, 4K bytes of program memory is contained within the chip. To read external program memory of microcontroller sends a signal PSEN (program store enable). Data Memory (RAM) occupies a separate address space from Program Memory. In the 8051 family, the lowest 128 bytes of data memory are on-chip. External RAM (up to 64K bytes). In accessing the external RAM, microcontroller send RD signal (read) and WR (write).

MCS51 memory structure

8051 Microcontroller Architecture Memory
b. Memory Program
shows a map of the lower part of the program memory. After reset, the CPU begins execution from location 0000H. As shown in Figure 1.6, each interrupt is assigned a fixed location in program memory. Interrupt causes the CPU to jump to the location where to do a particular service. External Interrupt 0, for example, is assigned to location 0003H. If External Interrupt 0 is used, its service routine must begin at location 0003H. If the interruption is not used, the location service can be used for various purposes as the Memory Program.

Interrupt Map 8051 microcontroller
c. Data Memory
In the figure below shows the memory space of internal and external data on the 8051 family. CPU generates RD and WR signals as needed during external RAM accesses. internal data memory under the memory ram divided into three blocks, which is referred as the lower 128 bytes, 128 bytes of upper and SFR space. Internal data memory address always has a width of one byte of data. Directly addressing the above 7Fh will access a memory address, and indirect addressing above 7Fh will access a different address. Thus in the figure below shows the 128 bytes of the top and SFR space occupying the same address block, ie 80h to FFH, which they actually physically separated
The lower 128 bytes of RAM are grouped into several blocks, 32 bytes of RAM at the bottom, grouped into 4 banks, each consisting of 8 registers. Program instructions call out these registers as R0 through R7. Two bits in the Program Status Word (PSW) select which register bank is to be used. The use of registers R0 through R7 will make programming more efficient and shorter, when compared directly addressing.

Memori data internal

128 bytes of internal RAM under

All the locations under 128 bytes of RAM can be accessed either by using direct and indirect addressing. Top 128 bytes can be accessed only by indirect.

128 bytes of internal RAM for
d. Special Function Registers
A memory map is called a space special function register (SFR) is shown in the following figure. Note that not all addresses are occupied, and the addresses are not occupied are not allowed to be implemented. Read access to this address will generate random data, and write access will result in no apparent effect.

e. Accumulator
ACC is the accumulator register. Mnemonics for accumulator-specific instructions this can simply be abbreviated as A.

f. Register
Register B is used at the time opersi multiplication and division. In addition to the above purpose, this register can be used to register free.

g. Program Status Word.
PSW registers consist of information on the status of the program.

h. Stack Pointer
Pointer register stack has a width of 8 bits of data. This register will increase before the data is stored during the execution of the push and call. While the stack may be a place of RAM. Stack pointer starts at address 07h after a reset. This causes the stack to begin at location 08h.

i. Data Pointer
Data Pointer (DPTR) consists of a byte over (DPH) and lower byte (DPL). This function is intended to store data 16 bits. Can be manipulated as a 16-bit register or two 8-bit registers that stands alone.
Mapping Data Pointer
READ MORE - A microcontroller (MCU) is a small computer in a single integrated circuit consisting of a CPU is relatively simple combined with support functions su

Minimum System (sismin) microcontroller

Minimum System (sismin) microcontroller is an electronic circuit the minimum required for operation of microcontroller IC. Sismin This can then be connected with other circuits to perform certain functions. In the AVR microcontroller family, 8535 series is one series that is very widely used.

To create a series Atmel AVR 8535 sismin required several components, namely:
ATmega8535 microcontroller IC
XTAL 1 4 MHz or 8 MHz (XTAL1)
3 capacitor paper, two 22 pF (C2 and C3) and 100 nF (C4)
A 4.7 UF electrolytic capacitor (C12) 2 resistors of 100 ohms (R1) and 10 Kohm (R3)
1 button reset pushbutton (PB1)

In addition, of course, required power supply that can provide 5V DC voltage.

The series of minimum system is ready to receive the analog signal (ADC facility) on port A. Image of the circuit is as follows.
READ MORE - Minimum System (sismin) microcontroller

Automatic Voltage Regulator (AVR)

Automatic Voltage Regulator (AVR) in principle have the same function as the generator Brushess Rectifier's just that the AVR is designed to be able to automatically regulate and control the supply voltage on exiter to add tension out on the main stator. AVR of generator functions to regulate, control and monitor the voltage coming out from the main stator based on the principle of feedback / feed back where the output is monitored to control the input so that a proper balance between voltage out to the voltage reference. so the voltage coming out of the generator is always constant with various levels of load.

1. When generators are connected electrical load, the electric current will flow in the stator windings
and magnitude in accordance with the electrical load is connected.
2. With the current flowing in the winding with iron core, then the resulting line-style line
magnets in the stator surface.
3. Lines of magnetic force lines has properties opposite the line of magnetic lines of force
caused by the spinning rotor pole pole.
4. With this resistance from the rotor magnetic force is reduced, so that the voltage generated
by the stator windings is reduced.
5. Trends that will drop the voltage detected by sensing input of the AVR and
compared with the reference voltage that is set.
6. With a voltage drop is smaller then the comparison with the reference voltage
so as soon as possible with the current AVR provides additional boost exciter.
7. The increase in current in the stator exciter effect on the resulting voltage exciter rotor.
And the effect is also against the currents to the main rotor, until the magnetic field generated
also increases.
8. The addition of a line equivalent to lines of magnetic force lines of resistance lines of force generated
stator winding currents.
9. Thus terbangkit voltage magnitude will remain.
10. Vice versa, if there is penguranganan weights, resistance of magnetic force become
smaller and with this trend will grow because the line voltage lines of force in
excessive main rotor.
11. The trend increase in voltage is detected by sensing input of the AVR and comparable
with a reference voltage that is set.
12. With tension rising, the ratio of voltage to be larger than the voltage
reference, so as soon as possible AVR reduces the flow in the exciter stator windings with
reduce the voltage exsitasi.
13. This will reduce the current in main winding rotor, until the magnetic force field down
for resistance to fall.
14. It can be concluded that the AVR will be able to adjust automatically increase and decrease flow so that the voltage generated exsitasi will remain with the various levels
READ MORE - Automatic Voltage Regulator (AVR)

Main function of the UPS

Uninterruptible power supply (UPS abbreviated) is a device that typically uses a battery backup as an alternative power ration, to May provide uninterrupted power supply for electronic devices attached. UPS is an electrical power supply system which is very important and necessary as well as serve as a fortress of power failure and damage to systems and hardware. UPS systems will become a very important and very necessary in many telecommunications service providers, information services, Internet service providers and more. Can imagine how big their losses related to power failure if the system is not protected by UPS.

description :
Transformer: Min 4 ampere or more
Diode|Dioda: Min 5 ampere or more
Irfz 44: Paste cooling plate

When normal PLN Electricity, of the adapter (the series of the most left) will produce voltage 12 - 13 volt / 5 ampaere. This voltage is used to fill mengoprasikan UPS batery and therefore this UPS if you plan to load a higher modifikasilah of this series that have a higher ampere. PLN electricity when dead, the source voltage in the switch to akan bateray

When electricity PLN suppressed, the source voltage will switch to the battery. ups that may be living longer while the power off, use battery who have ampere / hour high (large) or can also install some of the ways in parallel battery

UPS serves to ensure that electronic devices will still get power when a sudden flow of electricity to die. UPS will be automatically switched to the speed of 0.004 seconds of electric current to power the batteries, so that electronic devices remain lit.

UPS is a lot used primarily for electronic devices that need to be constantly on during the work, such as a PC (personal computer). The electric current sudden death also can result in damage to computer equipment. We know that PLN often conduct electrical current extinction without prior notice, or make cuts in business hours.

From the characteristic wave UPS can be divided into 2 parts, namely:

1. UPS Sin wave (sine) wave forms such as electricity PLN

2. UPS step-square/modified sinwave, square waveform

Main function of the UPS
1. Can provide temporary electrical energy when a power failure at the main power.
Provide adequate time opportunity to immediately turn on the main electricity generator as a substitute.
2. Provide adequate time opportunity to immediately back up your data and secure the [operating system] (OS) to perform shutdown procedures when the main power outages.
3. Securing computer systems from electrical disturbances that can disrupt a computer system in the form of damage to software, data or hardware damage.
4. UPS automatically to perform the stabilization voltage when the input voltage changes so that the output voltage used by the computer system in the form of the stable voltage.
5. UPS can do the diagnosis and management of his own making it easier for users to anticipate if there will be disruption to the system.
User friendly and easy in installation.
Users can control the UPS via a LAN network by adding a few accessories are required.
9. Can be integrated with the Internet network.
10. Notification in case of failure by setting the UPS management software.
READ MORE - Main function of the UPS

Arduino Severino microcontroller electronics

Price original Arduino board is still fairly Italy relatively expensive for some people. But that does not mean it is a barrier to learning and trying to use the Arduino microcontroller electronics. If you can make their own PCBs, you can create single-side PCB Arduino using PCB design.

For those of you who have not used to making PCBs or did not get to make your own, we've provided a kit called Arduino Severino which can be purchased at our store. Severino is the Arduino board in the PCB single side which is relatively cheap manufacturing cost. Not using a USB interface and using an ATmega8 chip easily available in the market with cheaper prices than ATMega328. So the price of the kit Severino become cheaper than Arduino Duemilanove or Uno.

The position pin header on the Arduino Severino exactly as Duemilanove or Uno, which can be fitted Arduino shield in the market.

If you want to try Arduino with a lower cost, or require additional Arduino board and wanted to press charges, please try to board Severino.
READ MORE - Arduino Severino microcontroller electronics

Nova Power NiMH battery

Pilotage "Nova Power" NiMH battery packs are designed, selected, and assembled specifically to provide the highest level of reliability and power to your model. The battery cells in our Nova Power packs offer the optimal balance between high output power, weight, and long cycle life. A few of the outstanding features of our battery packs are:
Stable output voltage at high discharge rates
Low internal resistance, minimal cell heating while discharging
Excellent power supply for r/c models
Long cycle life

2/3A 4.8V Pilotage Nova Power1600mAh NiMH battery pack.

This battery pack is designed to supply stable power to the Rx for GP model aircraft. The pack is in stick shape with 4 2/3A cells in a row.

Prior to using this battery pack it is essential to fully charge

Attention: Note the polarity when connecting the battery pack to the Rx. Not following the proper polarity of connections risks damaging the electronic components of your Rx and/or creating a fire hazard.

Package contents: 1pc battery pack w/ wire and connector

Technical parameters:

Operating voltage, V: 4.8
Capacity, mAh: 1600
Number of cells, pcs: 4
Maximal charge current, A: 0.16
Length, mm: 67
Width, mm: 28
Height, mm: 17
READ MORE - Nova Power NiMH battery