Breadd Board.....

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How to Use Breadd Board.....

BREAD BOARD....

A breadboard (protoboard) is a construction base for prototyping of electronics. The term is commonly used to refer to solder fewer breadboards (plug board).

Because the solderless breadboard does not require soldering, it is reusable. This makes it easy to use for creating temporary prototypes and experimenting with circuit design. Older breadboard types did not have this property. A stripboard (veroboard) and similar prototyping printed circuit boards, which are used to build permanent soldered prototypes or one-offs, cannot easily be reused. A variety of electronic systems may be prototyped by using breadboards, from small analog and digital circuits to complete central processing units (CPUs).

Connections on Breadboard

Breadboards have many tiny sockets (called 'holes') arranged on a 0.1" grid. The leads of most components can be pushed straight into the holes. ICs are inserted across the central gap with their notch or dot to the left.

Wire links can be made with single-core plastic-coated wire of 0.6mm diameter (the standard size). Stranded wire is not suitable because it will crumple when pushed into a hole and it may damage the board if strands break off.

The diagram shows how the breadboard holes are connected:

The top and bottom rows are linked horizontally all the way across as shown by the red and black lines on the diagram. The power supply is connected to these rows, + at the top and 0V (zero volts) at the bottom.

I suggest using the upper row of the bottom pair for 0V, then you can use the lower row for the negative supply with circuits requiring a dual supply (e.g. +9V, 0V, -9V).

The other holes are linked vertically in blocks of 5 with no link across the centre as shown by the blue lines on the diagram. Notice how there is separate blocks of connections to each pin of ICs.

Large Breadboards
On larger breadboards there may be a break halfway along the top and bottom power supply rows. It is a good idea to link across the gap before you start to build a circuit, otherwise you may forget and part of your circuit will have no power! 

Building a Circuit on Breadboard

Converting a circuit diagram to a breadboard layout is not straightforward because the arrangement of components on breadboard will look quite different from the circuit diagram.

When putting parts on breadboard you must concentrate on their connections, not their positions on the circuit diagram. The IC (chip) is a good starting point so place it in the centre of the breadboard and work round it pin by pin, putting in all the connections and components for each pin in turn.

The best way to explain this is by example, so the process of building this 555 timer circuit on breadboard is listed step-by-step below.

The circuit is a monostable which means it will turn on the LED for about 5 seconds when the 'trigger' button is pressed. The time period is determined by R1 and C1 and you may wish to try changing their values. R1 should be in the range 1k to 1M.

Time Period, T = 1.1 × R1 × C1

IC pin numbers     

IC pins are numbered anti-clockwise around the IC starting near the notch or dot. The diagram shows the numbering for 8-pin and 14-pin ICs, but the principle is the same for all sizes.

Components without suitable leads

Some components such as switches and variable resistors do not have suitable leads of their own so you must solder some on yourself. Use single-core plastic-coated wire of 0.6mm diameter (the standard size). Stranded wire is not suitable because it will crumple when pushed into a hole and it may damage the board if strands break off.

Building the example circuit

Begin by carefully insert the 555 IC in the centre of the breadboard with its notch or dot to the left.

Monostable Circuit on Breadboard

Then deal with each pin of the 555:

1.     Connect a wire (black) to 0V.

2.     Connect the 10k resistor to +9V.
Connect a push switch to 0V (you will need to solder leads onto the switch)

3.     Connect the 470 resistor to an used block of 5 holes, then...
Connect an LED (any colour) from that block to 0V (short lead to 0V).

4.     Connect a wire (red) to +9V.

5.     Connect the 0.01µF capacitor to 0V.
You will probably find that its leads are too short to connect directly, so put in a wire link to an unused block of holes and connect to that.

6.     Connect the 100µF capacitor to 0V (+ lead to pin 6).
Connect a wire (blue) to pin 7.

7.     Connect 47k resistor to +9V.
Check: there should be a wire already connected to pin 6.

8.     Connect a wire (red) to +9V.

Finally...

• Check all the connections carefully.
• Check that parts are the correct way round (LED and 100µF capacitor).
• Check that no leads are touching (unless they connect to the same block).
• Connect the breadboard to a 9V supply and press the push switch to test the circuit.

If your circuit does not work disconnect (or switch off) the power supply and very carefully re-check every connection against the circuit diagram. 

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An electric motor is an electric machine that converts electrical energy into mechanical energy.
In normal motoring mode, most electric motors operate through the interaction between an electric motor's magnetic field and winding currents to generate force within the motor. In certain applications, such as in the transportation industry with traction motors, electric motors can operate in both motoring and generating or braking modes to also produce electrical energy from mechanical energy.
Found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives, electric motors can be powered by direct current (DC) sources, such as from batteries, motor vehicles or rectifiers, or by alternating current (AC) sources, such as from the power grid, inverters or generators. Small motors may be found in electric watches. General-purpose motors with highly standardized dimensions and characteristics provide convenient mechanical power for industrial use.

Steps to Follow

The largest of electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings approaching a megawatt.

• Electric motors may be classified by electric power source type, internal construction, application, type of motion output, and so on.
• Devices such as magnetic solenoids and loudspeakers that convert electricity into motion but do not generate usable mechanical power are respectively referred to as actuators and transducers.
•  Electric motors are used to produce rotary or linear torque or force.

Note:

Found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives, electric motors can be powered by direct current (DC) sources, such as from batteries, motor vehicles or rectifiers, or by alternating current (AC) sources, such as from the power grid, inverters or generators. Small motors may be found in electric watches. General-purpose motors with highly standardized dimensions and characteristics provide convenient mechanical power for industrial use.

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Transistor......

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Transistors

The name transistor comes from the phrase \transferring an electrical signal across a

resistor".

Transistors are active components and are found everywhere in electronic circuits. They are used as amplifiers and switching devices. As amplifiers, they are used in high and low frequency stages, oscillators, modulators, detectors and in any circuit needing to perform a function. In digital circuits they are used as switches. 

There is a large number of manufacturers around the world who produce semiconductors (transistors are members of this family of components), so there are literally thousands of different types. There are low, medium and high power transistors, for working with high and low frequencies, for working with very high current and/or high voltages.

The most common type of transistor is called bipolar and these are divided into NPN and PNP types.

Their construction-material is most commonly silicon (their marking has the letter B) or germanium (their marking has the letter A). Original transistor were made from germanium, but they were very temperature-sensitive. Silicon transistors are much more temperature-tolerant and much cheaper to manufacture.

 Transistors are manufactured in different shapes but they have three leads (legs). 

The BASE - which is the lead responsible for activating the transistor.
The COLLECTOR - which is the positive lead.
The EMITTER - which is the negative lead.

Bipolar transistors have three leads: for base (B), emitter (E), and for collector (C). Sometimes, HF transistors have another lead which is connected to the metal housing. This lead is connected to the ground of the circuit, to protect the transistor from possible external electrical interference. Four leads emerge from some other types, such as two-gate FETs. High power transistors are different from low-to-medium power, both in size and in shape.

Biasing Of Transistotr...

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Diode...

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Diode is basically a 2 lead semiconductor in simple way a diode is semiconductor what has 2 lead. In operation, the diode is just like one way gate for the flow of electrons. It is the main property of the diode that it allows current to pass in only one direction. 

asic Symbol of Diode As:

Now the next concept is how diode works. To understand this. So, let start the next and very important concept of diode working:

How Diode Works:

After the brief introduction of the diode, now I tell you the basic ideas about its working principles. When we refer to diode work, two main points to be remembered are in which diode works normally. They are Forward Bias Diode and Reverse Bias Diode. Now here I tell you about the both properties of diode working accordingly.

Forward Bias Diode:

When the diode is connected to the battery in the way as shown in below figure, then what happen are electrons from the N-Side and Holes from the P-Side are forced towards the center by the electrical field supplied by the battery. Due to the combination of electrons and holes, the current pass through the diode. When a diode is arranged in this way as shown below, it is called the Forwards Biased Diode.

I hope your concept about the forward biasing working of diode will be very clear , now let come to the second property of diode working, that is Reverse Biasing.

Reverse Bias Diode:

When the diode is connected to the circuit or battery as shown in below figure, then what happens is , holes in the N-side are forced to the left while electrons in the P-side are forced to the right. This process results in an empty zone around the PN – Junction that is free of any charge carrier creating a Depletion Region. This depletion region acts like an insulator which prevents the current from flowing through the diode. When a diode is arranged in this manner, then it Is called Reverse Biased diode.

Points about the working Principle of Diode:

1.      As stated earlier that the diode is just like one way gate, so it does not work all the time.

2.      For silicon diode, an applied voltage of 0.6 V or greater needed, otherwise the diode conduction will not occur and diode will not work.

This feature is useful in forming a voltage-sensitive switch

PN Junction Diode:

A PN Junction diode is formed by joining the n-type and p-type silicon. In practice, as the n-type (Silicon) Si crystal is being grown, the process is abruptly altered to grow p-type Si crystal. Finally, a glass or plastic coating is placed around the joined crystal.

The P side of the PN Junction diode is called anode and the N Side is called the Cathode of the PN Junction Diode. When the anode and cathode of a PN-junction diode are connected to external voltage such that the potential at anode is higher than the potential at cathode, the diode is said to be forward biased.

In a forward-biased diode current is allowed to flow through the device.

Reverse Biased Diode:

When potential at anode is smaller than the potential at cathode, the diode is said to be reverse biased. In a reverse-biased diode current is blocked.

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WHAT IS STEPPER MOTOR

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The Stepper   motor consist     of  a    permanent    magnetic rotating   shaft   is  called  the rotor,    and electromagnets on the stationary portion that surrounds the motor, called the stator. Figure 1  complete rotation of a stepper motor. At position  , we can see that the   rotor is   beginning at the   upper electromagnet, which is currently active (has voltage applied to it). To move the rotor clockwise (CW), the upper  electromagnet is deactivated and the right electromagnet is activated, causing the rotor to move 90 degrees  Clock Wise CW, aligning itself with the active magnet.  Process        is  repeated  in  the   same manner at the south and west    electromagnets until we once again reach the starting positions

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Three Phase System

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Why we use Three-phase not four phases or other

Why we use Three-phase not four phase or other

Three phase power has

several advantages over

single phase power,

including smaller

Transformer size and weight,

and simplified motor construction. Four phase

power, which is actually two

phase power with the

phases in quadrature (90°

apart), doesn't really offer

any advantage over three phase power but requires an

extra conductor. Some

experimental work has been

done with 6 and 12 phase

power, but these have never

been put into common usage. When you consider

the cost of long transmission

lines from the power source,

three phase power is the

best alternative.

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