electronics and communication engineering ec&pc lab

Electronics and Communication Engineering ECPC Lab

Narsimha Reddy Engineering College Page -1

1. COMMON EMITTER AMPLIFIER

AIM: To design a Single stage CE amplifier with following specifications and to

study the frequency response of amplifier, calculate voltage gain and

bandwidth from the response. DESIGN SPECIFICATIONS:

VCC = 12V, IC = 2mA, VCE = 5V,AV = 100,hfe = 180, hie = 9 KΩ

RL = 1KΩ, S = 11, Silicon NPN Transistor SOFTWARE USED: Multisim V10.

CIRCUIT DIAGRAM:

DESIGN PROCEDURE:

AV = hfexRC

hie

RC

=4.7 KΩ

VE = VCC - ICRC - VCE

RE VE

I C I B



S 1 RB

RE

RB = Ω

VBB = VE + VBE

VBB VCC x R2

R1 R2

R R1 xR2

B R1 R2

Solve in equation (1) and (2)

- (1)

- (2)



PROCEDURE:

1. Switch ON the computer and open the multisim software.

2. Check whether the icons of the instruments are activated and enabled

3. Now connect the circuit using the designed values of each and every

component.

4. Connect the function generator with sine wave of 50 mV p-p as input at the

input terminals of the circuit.

5. Connect the Cathode Ray Oscilloscope (CRO) to the output terminals of the

circuit.

6. Go to simulation button click it for simulation process.

7. From the CRO note the following values

1. Input voltage Vi

2. Output voltage V0

3. Voltage gain AV = V0/Vi

4. Phase shift θ

8. To study the frequency response click the AC analysis, so that a screen

displays the following options

1. Start frequency

2. Stop frequency

3. Vertical scale

9. Assign the proper values for start frequency, stop frequency and vertical scale

according to the circuit requirements and observe the frequency response.

10. From the frequency response calculate the

maximum gain AVmax

lower cutoff frequency (f1) at AVmax - 3dB (decibel scale) value at AVmax/√2

(linear scale) value =20MHz

Higher cutoff frequency (f2) at AVmax - 3dB (decibel scale) at AVmax/√2

(linear scale) value =1MHz



OBSERVATIONS: From CRO:

1. Input voltage Vi =

2. Output voltage V0 =

3. 4. Voltage gain AV = V0/Vi =

From Frequency response:



1. Maximum gain AVmax

2. Lower cutoff frequency(f1) at AVmax - 3dB (decibel scale) value

at AVmax/√2 (linear scale)

3. Higher cutoff frequency(f2) at AVmax - 3dB (decibel scale) value


CALCULATIONS:

Band width (BW) =f2 - f1

RESULT:



2. COMMON SOURCE AMPLIFIER

AIM: To design a Single stage Common Source JFET amplifier with following

specifications and to study the frequency response of amplifier, calculate

voltage gain and bandwidth from the response.

DESIGN SPECIFICATIONS:

AV = 8, Ri’ = 100 KΩ, VDS = 5 V; gm = 2.5x10

-3,

R0 = 3.3 KΩ, VGS = -1 V, ID = 4.5 mA, rd = 23 KΩ, VDD = 25 V. SOFTWARE USED:

Multisim V10.

CIRCUIT DIAGRAM:

DESIGN PROCEDURE:

A gmrd Rd

i. Determine Rd using rd Rd

V

Rd=1500Ω

ii. Determine Rs, by applying KVL around output

loop VDD = (RD + RS) ID + VDS

RS =1000 Ω

iii. Determine the R1, R2 as follows

Applying KVL around input loop



PROCEDURE:


2. Check whether the icons of the instruments are activated and

enable.

3. Now connect the circuit using the designed values of each and

every component.

4. Connect the function generator with sine wave of 50 mV p-p as

input at the input of terminals of the circuit.

5. Connect the Cathode Ray Oscilloscope (CRO) to the output

terminals of the circuit.



1. Input voltage Vi



4. Phase shift θ

8. To study the frequency response click the AC analysis, so that a

screen displays the following options

1. Start frequency

2. Stop frequency

3. Vertical scale

9. Assign the proper values for start frequency, stop frequency and

vertical scale according to the circuit requirements and observe

the frequency response.


maximum gain AVmax

lower cutoff frequency (f1) at AVmax - 3dB

(decibel scale) value at

AVmax/√2 (linear scale) =

Higher cutoff frequency (f2) at AVmax-3dB

(decibel scale) value at




OBSERVATIONS: From CRO:



3. Voltage gain AV = V0/Vi =


CALCULATIONS:

Band width (BW) = f2 - f1

=

RESULT:



3. TWO STAGE RC COUPLED

AMPLIFIER

AIM: To design a Two stage RC coupled amplifier with following

specifications and to study the frequency response of amplifier,

calculate voltage gain and bandwidth from the response. DESIGN SPECIFICATIONS:

125 < AV < 150, RB1 ≥ 50 KΩ, VCC = 12 V, AV1 = 0.995, AV2

= 150,

R0 = 3.3 KΩ, VCE = VCC/2 = 6 V, hie = 2.2 KΩ, IC = 1.5 mA, S = 11.

SOFTWARE USED: Multisim V10.

CIRCUIT DIAGRAM:

DESIGN PROCEDURE:

a) Design of IInd

- stage

Determine the

RE2 as follows

Apply KVL to the output loop of II-stage

VCC = IC RC2 + VCE + IC RE2 (IE ~ IC)

R

VCC

IC

RC 2

VCE

E 2 IC



b) Determine the R3

and R4 as follows

Apply KVL to input

loop

VBB2 = IB RB2 + VBE + IE RE2 [IB2 = IC/β]

VBE2 = 0.6 V

To find RB2 by using

S = 1

RB 2

RE 2

As we know that

VBB2 = V

CC x

R

4 x

R3 RB2 =

R3 R4

R3

R3

R3 R4

R

4

V V

CC

RB 2

BB 2

R3

R

VCC

RB 2

3 VBB2

R3 = Ω

R4

1

1

RB 2

R3

R4 = Ω



c) Design for Ist - stage

Determine the RE1 as

follows

Apply KVL to the output loop of Ist - stage

VCC = VCE + ICRE1 (IE ~ IC)

RE1 V

CC IV

CE

C

From the above equations find R1 and R2

VBB1 = VCC x

R2

x

R1

RB1 = R1 R2

R1 R2

R1 R1 R2

V V

CC

RB1

BB1

R1



PROCEDURE:


2. Check whether the icons of the instruments are activated and enable.


component.


input of terminals of the circuit.


circuit.


7. To study the frequency response click the AC analysis, so that a screen displays

the following options

1. Start frequency

2. Stop frequency

3. Vertical scale




according to the circuit requirements and observe the frequency response. OBSERVATIONS:

From CRO:

RESULT:



4 (a). CURRENT SERIES FEEDBACK AMPLIFIER

AIM: To plot the frequency of the feedback amplifier, to find the voltage and

bandwidth. APPARATUS REQUIRED:

1. Trainer Board.

2. CRO, with probe

3. Function Generator.

4. Resistors 1k, 10k, 4.7k, 470Ω.

5. Capacitors 0.1uf, 47uf.

6. Transistor BC107.

7. Patch chords.

CIRCUIT DIAGRAM:



PROCEDURE:

1. Connect the circuit as shown.

2. Keep the emitter resistance RE by passed by connecting the capacitor CE

across RE from the circuit. Apply the AC signal voltage to the input of the

amplifier from the signal generator. Keep the input voltage low and freq at

1KHz.

3. Now disconnect capacitor CE across RE from the circuit again measure the

voltage at the output.

4. Find the gain of the amplifier i.e. with feedback and without feedback.

5. Vary the frequency of the input signal from 50Hz to 1MHz and measure the

output at each value of frequency for with feedback and without feedback by

keeping the input voltage constant.

6. Plot the frequency response curve and calculate band width for with feedback

and without feedback.

EXPECTED GRAPH:

RESULT:



4 (b) . VOLTAGE SERIES FEED BACK AMPLIFIER

AIM: To design a voltage series feedback amplifier with following specifications and

to study the frequency response of amplifier, calculate voltage gain and

bandwidth from the response. DESIGN SPECIFICATIONS:

AVf = 0.995, hfe = 125, Ri ’= 50 KΩ, VCC = 12V, hie = 2.2 KΩ, IC = 1.5 mA,

VCE = 6 V SOFTWARE USED: Multisim V10

CIRCUIT DIAGRAM:

DESIGN PROCEDURE:

i. Determine the RE using AV

hfe

xRE

hfe

xRE

RS hie

hie

AV is calculated as follows

AVf

AV

AV

( 1)

1 AV

1 AV

AVf (1 + AV) = AV

AVf + AVf AV = AV



AV(1 - AVf) = AVf

AV

AVf

AVf

1

A 0.995 199

V 1 0.995

R AV xhie

E h fe

RE 199 x(22 x10

3 ) 3502 .4

125

RE = 3.5 KΩ

ii. Determine the RC by applying KVL around output loop

VCC = IC RC + VCE + IC RE

VCC = VCE + IC (RC + RE)

12 = 6 + (1.5 x 10-3

) [RC + 3.5 x 10-3

] RC = 0.5 KΩ

iii. Determine the R1 and R2 as follows

R1 is calculated using VBB R

B

R1

R1

VCC

XR

B

VBB

RB is calculated as follows

Let we know that

RI ' RB RIf

RIf = hie + hfe x RE

RIf = (22 x 103) + (125 x 3.5 x 10

3)

RIf = 439.7 KΩ

RI ' RB RIf



50K

RB

xRIf

RB RIf

RB = 56.41 KΩ

VBB is calculated by applying KVL around input loop

VBB = VBE + IB RB + IE RE

VBB = 0.6 + 0.676 + 5.25 = 6.52 V

VBB = 6.52 V

R VCC XRB

1 VBB

R (12)x(56.41x103 ) 103.82K

1 6.52

R1 = 103.82 KΩ

R R RB= 1 2

R1 R2

R2=123.59KΩ

R1 = 103.82 KΩ, R2 = 123.59 KΩ, RC = 0.5 KΩ, RE = 3.5 KΩ PROCEDURE:




component.



5. Connect the Cathode Ray Oscilloscope (CRO) to the out put terminals of the

circuit.


7. From the CRO note the following values 8. To study the frequency response click the AC analysis, so that a screen displays




1. Start frequency

2. Stop frequency

3. Vertical scale




maximum gain AVmax =

lower cutoff frequency (f1) at AVmax - 3dB (decibel scale) value

at AVmax/√2 (linear scale) =35v

Higher cutoff frequency (f2) at AVmax - 3dB (decibel scale)

value at AVmax/√2 (linear scale) =32v OBSERVATIONS: From CRO:




1. Maximum gain AVmax =

2. Lower cutoff frequency(f1) at AVmax-3dB (decibel scale) value

at AVmax/√2 (linear scale) =

3. Higher cutoff frequency(f2) at AVmax-3dB (decibel scale) value at


CALCULATIONS:

Band width (BW) = f2 - f1

= Hz

RESULT:



5. CASCODE AMPLIFIER

AIM: To design a Cascode amplifier with following specifications and to study the

frequency response of amplifier, calculate voltage gain and bandwidth from the

response. DESIGN SPECIFICATIONS:

VCC = 15 V, IE1 = IE2 = 1 mA, AVT = 100, f = 1 K Hz, RC = 4.7 KΩ, β1

= β2 = 100 SOFTWARE USED: Multisim V10.

CIRCUIT DIAGRAM:

DESIGN PROCEDURE:

Calculation of RE

Applying KVL to output loop

VCC = IC RC + VCE2 + VCE1 + IE RE

VCE1 = VCE2 ≤ VCC/3 = 15/3 =5

5 V IC = IE1 = 1 mA

Calculation of R1 and

R2 β1 = β2 = 100



IC

I B

I B

IC

10 3

100

I

VB1

3

R3

VB1 = VBE2 + VE1

= 0.7 + IE RE

I3 = mA

I2 = IB1 + I3

I

VB 2 V

B1

2

R2

Where VB2 = VBE2 + VE1

I1 = IB2 + I2

I1 = A

R

VCC

VB 2

1

I1

PROCEDURE:




component.

4. Connect the function generator with sine wave of 50mVp-p as input at the input

of terminals of the circuit.


circuit.







3. Voltage gain AV = V0/Vi =

4. Phase shift θ =



1. Start frequency

2. Stop frequency

3. Vertical scale




maximum gain AVmax

lower cutoff frequency (f1) at AVmax-3dB (decibel scale) value


Higher cutoff frequency (f2) at AVmax-3dB (decibel scale)

value at AVmax/√2 (linear scale) OBSERVATIONS: From CRO:




1. Maximum gain AVmax

2. Lower cutoff frequency(f1) at AVmax-3dB (decibel scale) value


3. Higher cutoff frequency(f2) at AVmax-3dB (decibel scale) value

at AVmax/√2 (linear scale) CALCULATIONS:

Band width (BW) RESULT:



6. WEIN BRIDGE OSCILLATOR

AIM: To study the frequency response of amplifier, calculate voltage gain and

Bandwidth from the response.


CIRCUIT DIAGRAM:

PROCEDURE:




component.


circuit.



1. Amplitude of the output wave form

2. Time period of the signal



OBSERVATIONS:

From CRO:



3. CALCULATIONS: 4.

Theoretically:

Where R =4.7kohms C =10uf 10u

f

1

=

2xxRxC

RESULT:



7. RC PHASE SHIFT OSCILLATOR

AIM: To study and determine the frequency of oscillations of RC phase shift

oscillator and verify with the theoretical value. COMPONENTS REQUIRED:

1) Transistor (BC107) - 1No.

2) Resistors (47 K,12 K,3.9 K,1 K) - 1No.

10 K - 3No.s

3) Capacitors (4.7 µF, 47 µF) - 1No.

1 µF - 3No.s

CIRCUIT DIAGRAM:

PROCEDURE:




component.


circuit.







OBSERVATIONS:

From CRO:



CALCULATIONS:

Theoretically:

Where R = 10K C =10uf

f 1 K RC

R

2xxRxCx 6 4K

RESULT:



8. CLASS A POWER AMPLIFIER AIM: To calculate the efficiency of Class A power amplifier.


COMPONENTS REQUIRED:

1. Transistor (SL-100) - 1No.

2. Resistors (47 K, 220 Ω, 33 KΩ,220 Ω, 1 KΩ) - 1No.

3. Capacitor (10 µF) - 2No.s

CIRCUIT DIAGRAM:

PROCEDURE:


2. Check whether the icons of the instruments are activated and

enable.

3. Now connect the circuit using the designed values of each

and every component.

4. Connect the function generator with sine wave of 0.3 V p-p

as input at the input terminals of the circuit


6. Note down the multi meter readings across the RL resistor.

(Vac and Idc)



7. Calculate the efficiency.

OBSERVATIONS:

From multimeter

Vac =6.198V

Idc =60.07mA Calculations:

Pdc = VCC x Idc

Pac = Vac2/RL

Pac

Pdc

RESULT:



9. CLASS B COMPLEMENTARY SYMMETRY AMPLIFIER

AIM: To observe the Cross over distortion of Class B complementary symmetry

power amplifier. SOFTWARE USED: Multisim V10.

APPARATUS REQUIRED:

1. Function generator

2. Cathode Ray oscilloscope (CRO)

3. Regulated power supply (0-30V)

4. Transistor (2N3905, 2N3904) - 1No.

5. Resistor (1KΩ) - 1No.

6. Connecting wires

7. CRO probe

CIRCUIT DIAGRAM:

PROCEDURE:






component.

4. Connect the function generator with sine wave of 30mV p-p as input at the



circuit.


7. Observe the cross over distortion in the CRO.

OBSERVATION:

RESULT:



10. COMMON BASE AMPLIFIER


bandwidth from the response.


CIRCUIT DIAGRAM:

PROCEDURE:


12. Check whether the icons of the instruments are activated and enabled


component.

14. Connect the function generator with sine wave of 50mVp-p as input at the input



circuit.



1. Input voltage Vi



4. Phase shift θ





1. Start frequency

2. Stop frequency

3. Vertical scale



OBSERVATIONS:

From CRO:



From Frequency Response:

1. Maximum gain AVmax =

2. Lower cutoff frequency(f1) at AVmax - 3dB (decibel scale) value

at AVmax/√2 (linear scale) =

3. Higher cutoff frequency(f2) at AVmax - 3dB (decibel scale)

value at AVmax/√2 (linear scale) =

RESULT:



I(B) 1. CLASS A POWER AMPLIFIER

AIM: To calculate the efficiency of Class A power amplifier.

APPARATUS REQUIRED:


2. Regulated power supply (0 - 30V)

3. Bread board

4. Transistor (SL - 100) - 1No.

5. Resistors (20 KΩ, 100 Ω) - 1No.

6. Capacitor (10 µF) - 1No.

7. Digital multi meter

8. Connecting wires

CIRCUIT DIAGRAM:

PROCEDURE:

1. Connect the circuit as per the diagram.

2. Connect the function generator with sine wave of 0.3 V p-p as input at the input


3. Note down the multi meter readings across the RL resistor. (Vac and Idc)

4. Calculate the efficiency.



OBSERVATIONS:

Calculations:

Pdc = VCC x Idc =

Pac = Vac2/RL =

Pac

Pdc

RESULT:



I(B) 2. Class C Power Amplifier

AIM To design and construct a class C tuned amplifier and obtain the frequency response

characteristics.

APPARATUS REQUIRED

CIRCUIT DIAGRAM

PROCEDURE

Connect the circuit as per the diagram.

Set the input voltage.

Vary the frequency of the input signal and note down the corresponding output voltage.

Tabulate the readings and calculate the gain in dB. Plot the graph frequency Vs Gain in dB



DESIGN:

Let frequency f = 10 kHz f = 1/2π√LC Let C = 0.1 μF then L = 2.5 mH.

MODEL GRAPH

RESULT



I(B) 3. SINGLE TUNED VOLTAGE AMPLIFIER

AIM: To study the frequency response curve of single tuned voltage amplifier and

calculate voltage gain and bandwidth from the response. APPARATUS REQUIRED:


2. Bread board.

3. Cathode Ray Oscilloscope

4. Regulated power supply (0 – 30 V)

5. Resistors (90 KΩ, 27 KΩ, 567 Ω, 10 KΩ) - 1No.

6. Capacitors (10 µF, 1 µF, 1 µF,100 µF) - 1No.

7. Inductors (1 mH) - 1No.

CIRCUIT DIAGRAM:

PROCEDURE:

1. Make the connections as per the circuit diagram

2. Connect the input terminals to the Function generator and set the input voltage

50 mV p-p at 1 KHz.

3. Keep the input voltage constant and vary the input frequency from 500 Hz to



1M Hz with steps and note down the output voltage(V0).

4. Calculate the gain of amplifier using formula gain= V

0

Vi

Gain in dB 20 log V

0

Vi

5. Plot the Gain in dB Vs frequency graph.

6. From the graph calculate the

Maximum gain AVmax =46.02db

Lower cutoff frequency(f1) at AVmax - 3dB (decibel scale) value=45khz

at AVmax/√2 (linear scale) = Higher

cutoff=52khz

frequency(f2) at AVmax-3dB (decibel scale)

value

at AVmax/√2 (linear scale) = 7.

Calculate the bandwidth BW = f2 - f1.=7khz

OBSERVATION TABLE:

Vin = 50 mV (constant)

Sl.no. Freq

V0 (V) AV = V0/Vi Gain in dB =

(Hz) 20 log(AV)

1 42

2 45

3 47

4 48

5 49.6

6 50

7 52

8 55



EXPECTED GRAPH:

RESULT:



I (B) 4(a). HARTLEY OSCILLATOR

AIM: To calculate the frequency of oscillator of Hartley oscillator theoretically as

well as practically. APPARATUS REQUIRED:

1. Bread Board.

2. CRO with probes.

3. Resistors100 k,10 k - 2No’s, 1 k.

4. Capacitors10 uf - 4No’s

5. Inductors (2 mH) - 2 No’s

6. Transistor BC107

7. Patch cards.

CIRCUIT DIAGRAM:

PROCEDURE:

1. Make the connections as shown in above diagram.

2. Connect the CRO at output terminals.



3. Observe and record the frequency of Oscillations of CRO.

4. Calculate the frequency of oscillations practically.

5. Calculate the frequency of oscillations theoretically by using the formula

Where LT = L3 + L2 ;

L3 = 2 mH, L2 = 2 mH, C = 10 uF

6. Draw the wave form on normal graph sheet indicating the amplitude and time

period. EXPECTED GRAPH:

CALCULATIONS: Theoretical calculations:

Where LT = L3 + L2 ;

L3 = 2 mH, L2 = 2 mH, C = 10 uF

Practical calculations: T= F = 1/T =

RESULT:



I(B) 4(b). COLPITTS OSCILLATOR

AIM: To calculate the frequency of Colpitts oscillator theoretically as well as

practically. APPARATUS REQUIRED:

1. Bread board.

2. CRO with probes.

3. Patch cards

4. Resistors (100 k, 10 k – 2 No’s, 1 k.)

5. Capacitors (10 uf - 3No,100 nF - 2No’s)

6. Inductors107 mH, 2 mH.

7. Transistor BC107

8. Patch cards.

CIRCUIT DIAGRAM



PROCEDURE:

1. Make the connections as shown in above diagram.

2. Connect the CRO at output terminals.

3. Observe and record the frequency of Oscillations on CRO.

4. Calculate the frequency of oscillations practically.

1. Calculate the frequency of oscillations theoretically by using the formula

f

2 xx1

L1CT

C

C1

xC2

T C1 C2

where L1 = 2 mH

2. Draw the wave form on normal graph sheet indicating the amplitude and time

period IDEAL GRAPH:



CALCULATIONS: Theoretical calculations:

C

C1

xC2

T C1 C2

where L1 = 2 mH

Practical calculations: T = F = 1/T =

RESULT:



I(B) 5. DARLINGTON PAIR AMPLIFIER



APPARATUS REQUIRED:

1. Bread board

2. Function Generator



5. Transistor (BC558BP) - 2No.

6. Resistors (100 Ω, 100 kΩ, 6.8 kΩ, 150 kΩ, 2.2 kΩ, 2.2 kΩ) - 1No.

7. Capacitors(100 nF, 10 µF, 1µF) - 1No.

8. Connecting wires

9. CRO probes

CIRCUIT DIAGRAM:



PROCEDURE:

1. Connect the circuit as per the circuit diagram

2. Now connect the function generator to the input terminals of the amplifier

circuit and keep the input voltage constant i.e., 30 mV, 1KHz.

3. Connect the CRO to the output of the amplifier

4. By varying the input frequency from 50 Hz to 100 MHz in steps take the output

voltages from CRO.

5. Then calculate Voltage gain AV = V

O

Vi

In dB magnitude 20log V

O

Vi

6. Then plot frequency Vs gain in dB on semilog sheet.

7. From semilog sheet find bandwidth (fH - fL)

Band width = fH - fL



EXPECTED GRAPH:



CALCULATIONS: Band width=fh-fL

=

990Hz

RESULT:



I(B) 6. MOS AMPLIFIER



APPARATUS REQUIRED:

10. Bread board




14. MOSFET (2N7000) - 1No.

15. Resistors (4.7MΩ, 1kΩ, 1kΩ, 500Ω, 2.2MΩ) - 1No.

16. Capacitors(1µF, 1µF, 100µF) - 1No.

17. Connecting wires

18. CRO probes

CIRCUIT DIAGRAM:



PROCEDURE:


2. Now connect the function generator to the input

terminals of the amplifier circuit and keep the input

voltage constant i.e., 30 mV, 1KHz.

3. Connect the CRO to the output of the amplifier

4. By varying the input frequency from 50 Hz to 100

MHz in steps take the output voltages from CRO.

5. Then calculate Voltage gain AV = V

O

Vi

In dB magnitude 20log V

O

Vi

6. Then plot frequency Vs gain in dB on semilog sheet.

7. From semilog sheet find bandwidth (fH - fL)

Band width = fH - fL=236-5=231khz

EXPECTED GRAPH:

RESULT:



1. LINEAR WAVE

SHAPING

(a) RC HIGH PASS

CIRCUIT

AIM: 1. To draw the response of High Pass RC Circuit for the

given square wave input.

2. Calculate the Percentage of Tilt.

APPARATUS REQUIRED:

1. Capacitors 1μf - 1 No.

0.1μf – 1 No.

0.01μf – 1 No.

2. Resistor 10 kΩ - 1 No.


4. Bread board Trainer

5. CRO & Connecting wires

CIRCUIT DIAGRAM:

PROCEDURE:

1. Connect the circuit as shown in figure.

2. Apply square wave input with voltage of 5V &

frequency of 1 KHz.

3. Observe the reading of out put on CRO by placing

different capacitors of values like

1μf, 0.1μf, 0.01μf.

4. Note down the reading of V1& V11(marked in



expected waveforms) for each capacitor.

5. Find the percentage of tilt of RC high pass circuit.

6. Compare theoretical & practical values of response of

RC high pass circuit. OBSERVATIONS:

S.No. R(KΩ) C(µf) RC T(msec) Vo(V) condition

2 1

2 10

3 100

THEORETICAL CALCULATIONS:

T = RC; Percentage tilt =

T

X 100

2RC

Step 1: R=10kΩ ; C = 1μF. ; V = 5V;

T

% tilt =

X 100 = 5 %

2RC

T = 0.001 Sec. ; RC = 0.01 Sec. ; (RC >>T)

Step 2: R=10 KΩ ; C=0.1 μf; V=5V

T

% tilt =

X 100 = 50 %

2RC

T = 0.001 Sec. ; RC = 0.001 Sec. ; (RC =T)

Step 3: R=10 KΩ ; C=0.01 μf; V=5V

T

% tilt =

X 100 = 500 %

2RC

T = 0.001 Sec. ; RC=0.0001 (RC << T)



EXPECTED WAVEFORMS:



RESULT:



(b) RC LOW PASS CIRCUIT AIM:

1. To draw the response of Low Pass RC Circuit for the given square wave input.

2. Calculate the Rise time (tr). APPARATUS REQUIRED:

1. Capacitors 1μf – 1, 0.1μf – 1, 0.01μf – 1

2. Resistor 1 kΩ - 1



5. CRO & Connecting wires CIRCUIT DIAGRAM: PROCEDURE:

1. Connect the circuit as shown in figure.

2. Apply square wave input with voltage of 5V & frequency of 1 KHz.

3. Observe the reading of output on CRO by placing different capacitors of values

like 1μf, 0.1μf, 0.01μf.

4. Note down the reading of V1 & V2 (marked in expected wave forms) for

each capacitor.

5. Find the Rise time.

6. Compare the theoretical & practical values.



OBSERVATIONS:

S.No. R(KΩ) C(µf) RC T(msec) Vo(V) condition

2 1

2 40

3 100

CALCULATIONS:

a) Theoretical:

V2 = V tan h(x) where x = T here V = 5V

2 4RC

Case – 1: T << RC

R = 1 KΩ ; C = 10 μF ; RC = 0.01; T = 0.001

x = T

4RC

V2 = V tan h (x) =

2

V2 =0.0625. V

Rise time (tr) = 2.2 (RC) = 2.2 ( 1X103X10X10

-6)

tr = 22 msec

Case – 2: T = RC

R = 1 kΩ ; C = 1 μf;RC = 0.001; T = 0.001

x = T 0.25

4RC

V2 = V tan h (x) =

2

V2 =

Rise time (tr) = 2.2 (RC) =



Case – 3: T >> RC

R = 1 kΩ ; C = 0.1 μF ;RC = 0.0001; T = 0.001; T>>RC

x = T

4RC

V2 = V tan h (x) = 5 tan h (2.5) = 2.46653

2 2

V2 =

Rise time (tr) = 2.2 (RC) =



EXPECTED WAVEFORMS RESULT:



2 (a). NON-LINEAR WAVE SHAPING - CLIPPERS

AIM: To observe the output wave form for various types of Clipping circuits. APPARATUS:

1. Diodes (1N4007) -2 Nos

2. Resistors (1 KΩ -1 No)


4. Bread board trainer

5. Cathode Ray Oscilloscope (CRO)

6. Connecting Wires. CIRCUIT DIAGRAM: 1. Shunt Positive Clipper:

2. Shunt Negative Clipper:



3. Negative Bias series Clipper:

4. Positive bias series Clipper:

5. Double ended shunt clipper:

PROCEDURE:

1. Make the circuit connections as per circuit diagram

2. Set the sinusoidal input wave form with magnitude of 5 volts and frequency of 1KHz in

the function generator

3. Apply sinusoidal input from function generator to the circuit.

4. Sketch the respective output waveforms.

5. Repeat above procedure for each circuit.



EXPECTED WAVE FORMS:

Positive clipper: Negative clipper:

Double ended shunt clipper:

RESULT:



2 (b). NON-LINEAR WAVE SHAPING - CLAMPERS

AIM: To observe the output wave form for various types of Clamping circuits. APPARATUS:

1. Diodes (1N4007)-1.No.s

2. Resistors (1 kΩ -1)

3. Capacitor - 10µf



6. Cathode Ray Oscilloscope (CRO)

7. Connecting Wires CICRUIT DIAGRAM:

1.Positive peak clamper

2.Negative peak clamper



3. Positive peak bias clamper

4.Negative peak bias clamper

PROCEDURE:

1. Make the circuit connections as per circuit diagram

2. Set the sinusoidal input wave form with magnitude of 5 volts and frequency of

1KHz in the function generator

3. Apply sinusoidal input from function generator to the circuit.

4. Sketch the respective output waveforms.

5. Repeat above procedure for each circuit.



EXPECTED WAVE FORMS



RESULT:



3. SWITCHING CHARACTERISTICS OF A TRANSISTOR

AIM: Design transistor Switch by using the following specifications:

VCC = 5V, VBB = -4V, ICSat = 4mA, hfe=20, VBECutoff = -1, IB=1.5 IBmin.

APPARATUS REQUIRED:

1. Transistor (SL100) - 1 No.

2. Resistor 6.8 kΩ, 33 kΩ, 1kΩ





PROCEDURE:

1. Connect the circuit as per circuit diagram.

2. Apply square wave of 5V with frequency of 1KHz from function generator.

3. Observe the input and output waveforms.



EXPECTED WAVEFORMS: RESULT:



5. BISTABLE MULTIVIBRATOR AIM: To observe the waveforms of Bistable Multivibrator at base and collector of the

transistors and verify different states. APPARATUS REQUIRED:

1. Transistor (BC-107) – 2No’s

2. Resistors 1 kΩ-2 ; 10 kΩ-1No

2.7kΩ-2 ; 3.3kΩ-1No.

300kΩ-2

3. Capacitors 0.1μF – 3 No.

4. Diode (1N4007) - 1 No.

5. CRO & CRO Probes

6. Bread Board Trainer

7. Connecting wires CIRCUIT DIAGRAM



TRIGGER CIRCUIT:

PROCEDURE:


2. Find the values of voltages and currents for stable state with Multimeter.

3. First we have to check transistor Q1 is ON (or) OFF.

4. We should calculate the values of VCE1, VCE2, VBE and VBE2.

5. Apply negative voltage to the base of OFF Transistor.

6. Note down the values for VCE and VBE for Q1 & Q2

7. Observe the waveforms at base and collector terminals of both transistors. RESULT:



6.ASTABLE MULTIVIBRATOR AIM:- To observe the waveforms of Astable Multivibrator at base and collector of the

transistors and verify different states and find the frequency. APPARATUS REQUIRED:-

1. Transistors, (BC 107B) – 2 No.’s

2. Resistors- 10KΩ - 2, 1KΩ - 2

3. Capacitors- 100nf – 2No’s.

4. Cathode Ray Oscilloscope and CRO Probes



PROCEDURE:-

1. Connect the circuit as shown in the diagram.

2. Observe the Waveforms at the base and collector of both transistors.

3. Calculate the frequency

4. Compare theoretical and practical values. CALCULATIONS:

T = 1.38 RC

f =



EXPECTED WAVEFORMS:

RESULT:



7.MONOSTABLE MULTIVIBRATOR AIM: To observe the waveforms of Monostable Multivibrator at base and collector of the

transistors and find the Gate Width. APPARATUS REQUIRED:

1. Transistor (BC107B) - 2No’s.

2. Resistor R1 = 10kΩ, R = 12.5kΩ

3. Capacitor C = 100nF

4. CRO probes & CRO


6. Connecting wires. CIRCUIT DIAGRAM:



TRIGGER CIRCUIT:

PROCEDURE:


2. Assume Q1 – OFF, Q2 – ON

3. Measure VB1, Vc1, VB2, Vc2.

4. Measure quasi stable state voltage and current Q1 – ON & Q2 – OFF

5. Connect the base of ON transistor and find out the Vc1, Vc2, VB1, VB2,

6. Connect the base of OFF transistor and observe the waveform. CALCULATIONS: Gate Width T = 0.69RC

For VB1:

Amplitude for+ve =2v, -ve=10v, T=1msec

Fro VB2:

A for +ve =2v, for -ve =2v, T=1msec

For VC!:

A for +ve =3v, for -ve =1v, T=1msec

ForVC2:

A for +ve =5v, for -ve =7v, T=1msec EXPECTED WAVEFORMS:

RESULT:



8. SCHMITT TRIGGER AIM: To Study Schmitt Trigger circuit and observe waveforms. Find the UTP, LTP and

Hystersis. APPARATUS REQUIRED:


2. Transistor BC – 107B – 2No’s.

3. Resistor 12.5kΩ - 4 No’s

1kΩ, 1.5kΩ - 1No.

4. CRO & CRO Probes

5. Connecting wires CICRUIT DIAGRAM:

PROCEDURE:

1. Connect the circuit as shown in the diagram

2. Apply the Vcc=12V from bread board trainer

3. Apply the input 5V with a frequency 1KHz sinusoidal wave form and observe the

output wave form.

4. Find UTP, LTP and Hysterisis.



EXPECTED WAVEFORMS:

CALCULATIONS: UTP= LTP= Vi=UTP-LTP= UTP= LTP= VH=UTP_LTP=

RESULT:



9. UJT RELAXATION OSCILLATOR

AIM: To study UJT relaxation Oscillator with a frequency of 20 KHz and to observe

waveforms. APPARATUS REQUIRED:

1. UJT 2N2646 – 1 No.

2. Resistors – 1KΩ, 47 KΩ, 470 KΩ, 1 KΩ

3. Capacitor-1uf

4. Connecting wires


6. CRO & Probes

7. Connecting wires. CICRUIT DIAGRAM:

PROCEDURE:-


2. Observe the response of the circuit across the capacitor using CRO.

3. By placing resistor R1 and R2 at each step observe the O / P response VB1 & VB2 respectively.

4. Sketch the Waveform observed.

CALCULATIONS:

T1 = RC log 1

( = 0.5) T2 = (2+5C)VE

1-



EXPECTED WAVEFORMS:

RESULT:



10. BOOTSTRAP SWEEP CIRCUIT

AIM: To observe the characteristics of boot strap sweep generator

APPARATUS REQUIRED:

1. Transistor BC-107B - 2 no.s

2. Diode (1N4007) - 1No.

3. Resistors 220kΩ, 18kΩ, 2kΩ – 1no

4. Capacitor 10uF – 2No.s

100uF – 1No.

5. CRO



CIRCUIT DIAGRAM: PROCEDURE:


2. Generate a control square wave amplitude vc of 5v pp at 1khz Frequency and apply

into the circuit.

3. Observe the out put wave forms



EXPECTED WAVE FORMS: RESULT:



11. MILLER SWEEP CIRCUIT

AIM: To observe the characteristics of boot strap sweep generator

APPARATUS REQUIRED:

1. Transistor BC-107B - 1 no.s

2. Resistors 22kΩ, 1kΩ – 2no, 2kΩ

4. Capacitor 1uF – 1No.s

5. CRO



CIRCUIT DIAGRAM:

PROCEDURE:


2. Generate a control square wave amplitude vc of 5v pp at 500 Hz Frequency and apply

into the circuit.

3. Observe the output wave forms



CALCULATIONS:

For Input: A=10v T= 4 msec For output: A= T= Charging time= Dischrging time=



EXPECTED WAVE FORMS:

RESULT:

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