EXP-1

DIODE CLIPPING CIRCUITS

Aim: To design and test diode clipping circuits for peak clipping and peak detection.

Components required:

-Power Supply

-Diodes IN4007or BY127

-Resistors

Procedure:

Make the Connections as shown in the circuit diagram

Apply sinusoidal input Vi of 1 KHz and of amplitude 8V P-P to the circuit. Observe the output signal in the CRO and verify it with given waveforms.

Apply Vi and Vo to the X and Y channel of CRO and observe the transfer characteristic waveform and verify it.

I)Positive Clipping

Circuit: Circuit

Diagram:

R

8Vp-p

Waveforms:

3.3KD

Vi VoVR 2.4

V

Dept of E&C, CEC Analog Electronics Lab Manual

Transfer Characteristics:

To find the aluee of R:

Given: Rf =100Ω, Rr =100KΩ

Rf - Diode forward

resistance Rr - Diode

reverse resistance

R= =3.16KΩ

Choose R as 10 KΩ

Let the output voltage be clipped at

+3V Vomax =3V

From the circuit diagram,

Vomax = Vr+Vref

Where Vr is the diode drop =

0.6V Vref = Vomax -Vr

=3 - 0.7

Vref = 2.3 V

3.3K

BY127

Vi Vo

VR 2.4V

Dept of E&C, CEC Analog Electronics Lab Manual

II)Negative Clipping

Circuit: Circuit

Diagram:

R

Waveforms:

Trlnsfe r Chlrlcte ristcs:

Let the output voltage be clipped at

-3V Vomin = -3V

Vomin = -Vr+Vref

Vref = Vomin+Vr = -3 + 0.7

Vref = -2.3V

EXP-2

CLAMPING CIRCUITS

Aim: Design and test positive and negative clamping circuit for a given reference voltage.

Components required:

- Power Supply

- CRO- Signal Generator- Diode BY 127- Resistors- Capacitor

Design:

Rf – Diode forward resistance =

100Ω Rr – Diode Reverse

resistance = 1M Ω R = =

10KΩ

let T = 1ms

f(1KHz) Let RC =

10T

RC = 10ms

C = 1µF

R =

10KΩ

I) Positive Clamping

Circuits: Circuit

Diagram:

C

+ -

1mF

8Vp-p Vi

D BY127 R 10K Vo

Dept of E&C, CEC Analog Electronics Lab Manual

Waveforms:

II) Design a Clamping Circuit to Clamp Negative Peak at +3V:

C

+ -

1mF

8Vp-p Vi

D

R 10K Vo

Vref 3.6V

Waveforms:

Vo = +

Vref 3 = -0.7

+ Vref

Vref = 3.7

Dept of E&C, CEC Analog Electronics Lab Manual

III) Negative Clamping

Circuit: Circuit

Diagram:

C

+ -

1mF

8Vp-p Vi

D R 10K Vo

Waveforms:

EXP-3

Dept of E&C, CEC Analog Electronics Lab Manual

RECTIFIER CIRCUITS

Aim: To design and test Half wave, Full wave, Bridge Rectifer circuits with & without capacitor flter and determine the Ripple factor, Regulation & Efciency.

Components required:

- Resistors- Diodes- 12-0-12V Transformer- Capacitor

Calculations:

Assume RL = 4.7KΩ, C = 220µF

I) Half wave Rectifier:

1. Ripple Factor without Filter (Theoretical) = 1.21

2. Percentage Regulation = (Rf = Diode forward resistance)

3. Rectifer Efciency η = 40.6 %

4. Ripple Factor without Filter = (f = frequency = 50Hz)

II) Full wave Rectifier:

1. Ripple Factor without Filter = 0.48

2. Percentage Regulation = 3. Rectifer Efciency η = 81 %

4. Ripple Factor without Filter =

III) Bridge Rectifier:

1. Ripple Factor without Filter = 0.48

2. Percentage Regulation = 3. Rectifer Efciency η = 81 %

I)Half wave Rectifier without

Filter: Circuit Diagram:

230V 12V

IN 4001

230V/50Hz

AC

RL=4.7K Vo

0 0

Waveforms:

Peak output voltage

Vm= Vdc = =

Vrms = =

Vac = =

Ripple Factor =

Rectier efciency η = = = % Regulaton =

Dept of E&C, CEC Analog Electronics Lab Manual

Half wave Rectier with Filter:

230V 12V

IN 4001

230V/50Hz

AC

+ 220mF

-

RL=4.7K Vo

0 0

Waveforms:

Peak output Voltage

Vm = Ripple Factor =

=

Vdc = =

Vac = =

Vrms = =

Rectifer efciency η = = 2=

% Regulation =

Dept of E&C, CEC Analog Electronics Lab Manual

II) Full wave Rectifier without

Filter: Circuit Diagram:

D1

12V

230V/50Hz

AC

RL

4.7K

Vo

12V

D2

Waveforms:

(ms)

Vdc = =

Vrms = =

Vac = =

=

T/2 T 3T/2

η = = 2=

% Regulation =

(ms)

T/2 TT

3T/2

T/2

Dept of E&C, CEC Analog Electronics Lab Manual

III) Full wave Rectifier with

Filter: Circuit Diagram:

D1

12V RL

4.7K

C

220m

F

230V/50Hz AC Vo

12V

D2

Waveforms:

Vdc = =

Vac = = Vrms = =

η = = 2=

Dept of E&C, CEC Analog Electronics Lab Manual

Bridge Rectier without Filter: Circuit Diagram:

230V 12V

230V/50Hz AC

RL

Vo

0

Waveforms:

(ms)

Vdc = =

Vrms = =

Vac = =

=

η = = 2=

D1

D3

D4

D20

T/2 T 3T/2

% Regulation =

(ms)

T/2 TT 3T/2

T/2

Bridge Rectifier with

Filter: Circuit Diagram:

230V 12V

230V/50Hz AC

RL Vo

Waveforms:

Vdc = =

Vac = =

=

Vrms = =

η = = 2=

D1 D3D4 D2 +

-0 0 220m

F

Dept of E&C, CEC Analog Electronics Lab Manual

Procedure:

Make the Connections as shown in the circuit diagram

Apply 230V AC supply from the power mains to the primary of the transformer

Observe the voltage across secondary to get Vm , the peak value in CRO Use relevant formula to fnd Vdc and Vrms of both Full wave and Half wave

rectifer & draw the waveforms

Find out the Ripple factor, Regulation and Efciency by using the formula.

Conclusions:

EXP-4

R.C.PHASE SHIFT OSCILLATOR

Aim: To design and test the RC Phase shift Oscillator for the frequency of 1KHz.

Components required:

-Transistor (BC 107)

- Resistors- CRO

- Capacitors

Design:

VCC =

12V IC =

2mA

VRC = 40% VCC =

4.8V VRE = 10%

VCC = 1.2V VCE =

50% VCC = 6V

To find RC, R1, RE &R2

We Have,

VRC =

ICRC=4.8V RC

= 2.4KΩ

Choose RC = 2.2KΩ

VRE =

IERE=1.2V RE

= 600Ω

Choose RE = 680Ω

hfe = 100 (For BC

107) IB= =

20mA

Assume current through R1 = 10 IB & through R2 = 9 IB VR1 = VCC-VR2

= 10V

Also, VR1 =10 IB R1=10.1V

Dept of E&C, CEC Analog Electronics Lab Manual 10ESL37

R1= 50KΩ

Choose R1= 47KΩ

VR2 = VBE+VRE

= 0.7+1.2

= 1.9V

Also, VR2 =9 IB

R2=1.9V R2=

10.6KΩ

Choose R1= 12KΩ

To find CC & CE

XCE = = = 68Ω

For =

20Hz CE=

117

Choose CE = 220

XCC = = 220Ω

For = 20Hz

Choose CC =

47

Design of Selective Circuit:

Required of oscillations f = 1KHz

Take R= 4.7KΩ & C=0.01µF

Procedure:

Rig up the circuit as shown in the fgure

Observe the sinusoidal output voltage.

Vcc = 12V

R1 47KRc2.2K

C C C

Cin0.01mF

0.01mF

0.01mFBC 107

47mF

VoR

R2 12KCE 4.7K

R

4.7K

R

4.7KRE 68

0

220mF

Dept of E&C, CEC Analog Electronics Lab Manual 10ESL37

Measure the frequency and compare with the theoretical values.

Circuit Diagram:

Re seut:

Frequency

Theoretical: 1KHz

Practical:

1.5KΩ

SL100R11µF1µ

FSK100

1.5KΩ

EXP-5

CLASS ‘B’ PUSH-PULL AMPLIFIER

Aim: To design and test the performance of transformer less Class ‘B’ Push-Pull Amplifer and to determine its conversion efciency.

Components Required:

- Diodes IN 4001

- Transistor SL100, SK100

- Resistors- Capacitors

Circuit Diagram:

Vcc = 15V

Vi RL 470ΩVo

Design:

Given VCC = 15V, RL = 470Ω

VCE1 = VCE2 = =

7.5V

VB1 = VCE2 + VBE1 = 7.5 + 0.7 = 8.2V

Assume I1 = 5mA

R1 =

= 1.36KΩ

R2 =

=

1.36KΩ

ChooseR1

= R2

= 1.5KΩ

Dept of E&C, CEC Analog Electronics Lab Manual

Choose Ci = C2 = 1µF

Pi(dc) = VCC Idc

Po(ac) =

Efciency η =

Procedure:

Connect the circuit as shown in the circuit diagram.

Apply the input voltage Vi = 5V

Keeping the voltage constant, vary the frequency from 100Hz to 1MHz in regular steps and note down the output voltage in each case.

Plot the gain Vs Frequency graph.

Note down the dc current Idc

Calculate the efciency.

Observations:

Vi = 5V

Freq. in Hz Vo Gain= Gain in dB

= 20 log

50 Hz100 Hz200 Hz

500 Hz1KHz2KHz

3KHz5 KHz

10 KHz...

. 1MHz2 MHz

Result:

Efciency η =

EXP-6

AIM: To check the following applications of OP-AMP.

a) Inverting Amplifer. b) Non inverting amplifer.APPARATUS:

S.No

Name

Range / Value Quantity

1. Fixed power supply [- 15V – 0V – +15V] 1

2. OP-AMP A741C 13. Resistors 1K, 4.7K, 10K,

33KEach 1

4. Function generator -- 1

5. CRO -- 1

PROCEDURE:

INVERTING & NON - INVERTING AMPLIFIER:

1.Connect the circuit as shown in the fgure -1

2.Switch on the power supply and signal generator.

3.Apply a sinusoidal signal with peak to peak amplitude of 20mVat a frequency of 1KHz.

4.Note down the amplitude of O/P signal in the C.R.O.

5.Repeat the above steps for diferent values of Rf.

6.Repeat the above steps for the circuit of fg –2.

7.Tabulate the readings.

CIRCUIT DIAGRAM:

Inae rtng Ampuifie r: Non - inae rtng Ampuifie r:

INVERTING AMPLIFIER:

Vi = 20mV

S.NO

Rf

( )R1(

) V0 (mV) Gain = V0 / Vi

Theoretical Gain = (-Rf/R1)

1 4.7K 1K

2 10K 1K

3 33K 1K

NON-INVERTING AMPLIFIER:

Vi = 20mV

S.NO

Rf

( )R1(

)V0 (mV)

Gain= V0 / Vi

Theoretical Gain = (1+Rf/R1)

1 4.7K 1K2 10K 1K3 33K 1K

RESULT-

EXP-7

COLPITTS OSCILLATOR

AIM: To determine the frequency of oscillations of a given Colpitts Oscillator.

APPARATUS:

S.No

Name

Range / Value

Quantity

1. DC Regulated Power Supply (0-30V) 12. Resistors 560, 47 K Each 1

4. Resistors 4.7 K 2

5. Capacitors 100F, 0.047F Each 1

6. Decade Inductance Box -- 1

7. Decade Capacitance Box -- 2

8. CRO -- 1

PROCEDURE:

1. Connect the circuit diagram as shown in the fgure.

2. Switch on the power supply.

3. Connect the out put terminals to CRO.

4. Adjust the capacitances until a sinusoidal wave form is observed on the CRO.

5. Measure the time period of the sinusoidal wave form (T) and determine the Frequency (1/T).

6. Repeat the above steps for diferent values of L, C1 & C2.

2 LCeq

7. Tabulate the readings and compare with theoretical values

CIRCUIT DIAGRAM

TABULAR FORM:

S.NO.

L (mH)

C (F)

Practical

frequency (Hz)

Theoretical

Frequency (Hz)C1 C2

1

2

3

CALCULATIONS:

f0 (practical) =1/T Hz.

f0 (theoretical)

f 1

. [Where

C

C1 C2 ]0

eq

C1 C2

38EXP-8

WEIN BRIDGE OSCILLATOR

AIM: To determine the frequency of oscillations of a given Wein Bridge oscillator and compare it with the theoretical value.

APPARATUS:

S.No

Name

Range / Value Quantity

1. Fixed Power Supply [- 15V – 0V – +15V] 12. OP-AMP A741C 1

3. Potentiometer 47 K 1

4. Resistors 3.3 K , 220 Each 2

5. Resistors 12 K 1

6. Capacitors 0.047 F, 0.33 F Each 2

7. CRO. -- 1

PROCEDURE:

1.Connect the circuit as shown in the fgure.

2.Connect 0.047 F, and 3.3 K in place of C and R.

3.Connect the O/P to the C.R.O and observe the sinusoidal signal and measure its frequency.

4.Connect 0.33 F, and 220 in places of C and R.

5.Observe the sinusoidal signal and measure its frequency.

6.Tabulate the readings and Compare it with theoretical values

39CIRCUIT DIAGRAM:

TABULAR FORM:

S.NoCapacitan

ce C ( F )

Resistance R (Ω)

Theoretical

Frequency =1/2 RC (Hz)

PracticalFrequency=

1/T (Hz)

1

2

0.047

0.33

3.3K

220

FORMULAS:

Practical Frequency =Fо=1/T

Theoretical Frequency=1/2ΠRC

40

EXP-9

HARTLEY OSCILLATOR

AIM: To Determine the frequency of oscillations of a

Hartley Oscillator and compare it with the theoretical

values.

APPARATUS:

S.No

Name

Range / Value

Quantity

1. D.C Regulated Power Supply

(0 – 30V) 1

2. Resistors 1KΩ, 10kΩ, 47KΩ Each 1

3. Capacitors 0.22µF 2

4. Decade Capacitance Box -- 1

5. Decade Inductance Box -- 2

6. CRO -- 1

41

PROCEDURE:

1.Connect the circuit as shown in the fgure.

2.Connect the O / P of the oscillator to the C.R.O.

3.Adjust the Capacitance and Inductance Boxes until a

sinusoidal signal is observed in the CRO.

4.Determine the frequency of the wave form.

5.Determine the frequency by varying the capacitance in convenientsteps.

6.Tabulate the readings and compare the readings with the theoretical values.

CKT DIA.

TABULAR FORM:

Capacitance C ( F )

Inductance

( m H )Practical

Frequency (Hz)

Theoretical Frequency (Hz)

L 1 L 2

42

FORMULAS:

Theoretical Frequency f0 ΠLC

Practcal Frequency F =1/T