1. IDENTIFICATION ,SPECIFICATIONS,TESTING OF R,L,C COMPONENTS (COLOR CODES), POTENTIOMETERS,SWITCHES(SPDT,DPDT &DIP), COILS,GANG CONDENSERS, RELAYS,BREAD BOARD.

AIM: To identify the different component symbols.

 

APPARATUS: Resistors

Capacitors

Transformers

Semi conductors

Transistors

 

THEORY:

 

RESISTORS:

Opposition to flow of currents is called resistance. The elements having resistance are called resistors. They are of two types

1. Fixed resistor

2. Variable resistor

 

CAPACITORS:

Capacitors are used to store large amount of static current.

When they are included in circuit it acts open circuit. They are three types

1. Disk capacitor

2. Fixed capacitor

3. Variable capacitor

 

 

 

TRANSFORMERS:

Transformers are used to transfer the current.

They are of two types

1. Step up Transformer

2. Step down Transformer

 

SEMICONDUCTORS:

Semiconductors are partial conductors which conducts electricity partially through them.

They play major role in electronics.

1 P-N Junction diode

2. Zener diode

Semiconductor is a material for which the width of the forbidden gap between the valence band conduction is very small. As gap is every small valence electron acquire required energy to go in to the conduction band. These free electrons constitute of current under the influence of applied electric field. The energy band is time for semiconductor. They are a class of material whose electrical conductivity lies between that of a conductor and an insulator. The conductivity of a semiconductor lies in a range of10^5 and 10^-4siemens/meter.

 

INDUCTOR SPECIFICATIONS :

1. Inductance Value
   
2. Resistance
   
3. Capacitance
   
4. Frequency Value
   
5. Quality Factor
   
6. Power Losses
   
7. Current Ratings
   
8. Electro Magnetic Radiations
   
9. Temperature Coefficient
   

 

SWITCHES:

 

SPST: Single pole single through

SPDT: Single pole double through

DPST: Double pole single through

DPDT: Double pole double through

 

DIODES:

Diodes have more priority now a days. They are mostly used in developing electronic systems. They are

1. P-N Junction diode
   
2. Zener diode
   

   Zener diode is background biasing voltage. So it also called voltage requesting diode.
   

   
    

   TRANSISTORS:
   

   They are of 4 types
   

   1. BJT: Bi polar junction transistor again 2 types
   

NPN-BJT

PNP-BJT

Here B-base

C-collector

E-Emitter

2. FET: Field effect transistors again 2 types

P-Channel FET

N-Cannel FET

 

Here G-Gate terminal

D-Drain terminal

S-Source terminal

3. JFET: Junction field effect transistors they similar to FET.

4. MOSFET: Metal oxide semiconductor field effect transistor

These are of two types

a. Depletion MOSFET:

These are again classified into two types

N-Channel MOSFET

P-Channel MOSFET

Here ss is substrate

b. Enhancement MOSFET:

These are again classified into two types

N-Channel MOSFET

P-Channel MOSFET

 

Here G-Gate terminal

D-Drain terminal

S-Source terminal

ss-subsstrate

 

CIRCUIT DIAGRAM:

 

RESISTORS:

 

-fixed resistor

 

-variable resistor

CAPACITORS:

-fixed capacitor

-variable capacitor

 

INDUCTORS:

-Fixed inductor

 

Variable inductor

TRANSFORMERS:

 

Primarysecondary

SWITCHES:

SPST

SPDT

DPST

DPDT

SEMICONDUCTORS:

 

P-N Junction diode

Zener diode

 

BREAD BOARD

 

An experimental version of a circuit generally lay out on a flat board and assembled with temporary connections so that circuit elements may be easily substituted or changed. The name originates from the fact that early electrical circuits were actually wired on wood bread boards.

It is used to connect an electronic circuit temporarily for testing and experimentation.

A typical bread board is shown in fig.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RESISTOR COLOR CODE

 

The resistance value and tolerance of carbon resistor is usually indicated by color coding. Color bands are printed on insulating body. They consist of four color bands or 5 color bands & they are read from left to right.

 

A typical resistor with color bands is shown in figure

 

The above resistor has 4 color bands.

The first band represents first digit

The second band represent second digit

The third band represent multiplier (this gives the no. of zeros after the 2 digits )

The 4^th band represents tolerance in %

 

The color codes are presented in below table

COLOR		First digit for the 1st band		Second digit for the 2nd band		Multiplier digit for the 3rd band		Resistance tolerance
Black		0		0		10^0		-
Brown		1		1		10^1		±1%
Red		2		2		10^2		±2%
Orange		3		3		10^3		±3%
Yellow		4		4		10^4		-
Green		5		5		10^5		-
Blue		6		6		10^6		-
Violet		7		7		10^7		-
Gray		8		8		10^8		-
White		9		9		10^9		-
Gold		-		-		10^-1		±5%
Silver	-		-		10^-2		±10%
No color	-		-		-		±20%

-

 

If third band is gold the first two digit are multiplied by 10^-1

If the third band is silver the first two digits are multiplied by 10^-2

If the 4^th band is gold the tolerance is ±5%

If the 4^th band is silver is the tolerance is ±10%

If the 4^th band is no color the tolerance is
±20%

The numerical value associated with each color

 

B	B	R	O	Y	G	B	V	G	W
black	brown	red	orange	Yellow	green	blue	violet	gray	White
0	1	2	3	4	5	6	7	8	9

 

EXAMPLES:

The resistor has a color band sequence green, blue, brown and silver identify the resistance value.

 

 

 

1ST Band	2nd band	3rd band	4th band
1st digit	2nd digit	multiplier	tolerance
5	6	10^1	±10%

 

 

The resistance value=56x10^1±10%

=560Ω±10%

Therefore the resistance should be with in the range of 555Ω to 565Ω

 

SECIFICATIONS FO RLC COMPONENTS

 

RESISTOR:

 

1. Resistance value:

This is the value of the resistance expressed in ohms.

Ex: 10Ω, 1MΩ

2. Tolerance:

This is the variation in the value of the resistance i.e. expected from exact indicated value usually tolerance is represented in %

ex: 1%,2%,20%...

2. Power rating:

The power rating is very important in the sense that it determines the maximum correct that a resistor can withstand without being destroyed.

The power rating of resistor is specified as so many watts at a specific temperature such as one or two watts at 70 degree.

 

CAPACITOR:

1. Value of capacitance
   
2. Tolerance
   
3. Voltage rating
   
4. Temperature coefficient
   
5. Leakage resistance
   
6. Frequency range
   
7. Dielectric constant
   
8. dielectric strength
   
9. power factor
   
10. Stability
    

 

 

INDUCTOR;

 

Inductor value:

The inductance is defined as the ability of an inductor which opposes the change in current. It is denoted by the letter "L" and its unit is Henry(H).Ex:1H.2H…

Mutual inductance:

It is the ability of a varying current in one inductor L1 induced voltage in another inductor L2 near by .

It is represented by Lm and is measured in Henry.

M=K√ (L1XL2) H

Coefficient if coupling:

It is defined as the ratio of flux linkages between L1 and L2. To total flux produced by L1. It is represented by K and its typical value is 1.

K=Lm/√ (L1XL2)

 

Permeability:

It is denoted by micro's" and it is return as μ=B/H.

Where B=flux density

H=Flux intensity

 

 

PROCEDURE:

Different components can be identified by using their different symbols.

 

 

RESULT:

Components should be identified by using their symbols.