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NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.01
First order low pass filter
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Page 1 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Name of Technical Assistant:
Objective: For the first order low pass filter evaluate
1. High cut-off frequency
2. pass band gain
3. plot the frequency response of low pass filter
Apparatus: 1. Bread board
2. DC power supply ±12V
3. Function generator
4. Oscilloscope
5. multimeter
6. patch cords
Theory: An active filter is frequency selective circuit that passes electric signals of specific band of
frequencies and attenuates signal off frequencies outside this band depending on the type of
elements used in their construction filters may be classified as passive or active filters elements
used in passive filters are resistors, capacitors and inductors.
Active filter consists of active components such as op-amp, transistors with passive
elements.
Most commonly used filters are:
A.
Low pass filter
C.
Band pass filter
B.
Page 2 of 58
High pass filter
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
LOW PASS FILTER
It is a frequency selective circuit, which passes signals of frequency below its high cut-off
frequency (fh) and attenuates signals of frequency above fh.
Equation of high pass filter is
Vout /Vin =AF /1+J(f/fh)
……..1
Vout / Vin = AF / {1+(f/fh)2}1/2
………….2
Vin = Input signal voltage
Vout = output signal voltage
Vout / Vin = Gain of filter as a function of frequency
AF = 1+RF /R1 pass band gain of filter
F = frequency of input signal
fH= 1/2πRC = high cutoff frequency, 3-db frequency, cornet frequency operation of low pass
filter using equation 2
a.
at low frequencies f<fh
Vout / Vin
<AF
b.
at f = fh
Vout /Vin
=0.707*AF(approx.)
c.
at f>fh
Vout / Vin
=AF
Page 3 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
This ideal low pass filter has a constant gain AF from 0 to high cutoff frequency (fH) at fH the
gain is 0.707* Af and after fH it decreases at a constant rate with an increase in frequency i.e.
when input frequency is increased tenfold (one decade) the voltage gain is deviled by 10.
Gain (db) =20 log Vout/Vin i.e. Gain roll off rate is -20 db/decade.
This first-order low pass active filter consists simply of a passive RC filter stage providing a low
frequency path to the input of a non-inverting operational amplifier. The amplifier is configured
as a voltage-follower (Buffer) giving it a DC gain of one, Av = +1 or unity gain as opposed to the
previous passive RC filter which has a DC gain of less than unity. The advantage of this
configuration is that the op-amps high input impedance prevents excessive loading on the
filters output while its low output impedance prevents the filters cut-off frequency point from
being affected by changes in the impedance of the load.
While this configuration provides good stability to the filter, its main disadvantage is that it has
no voltage gain above one. However, although the voltage gain is unity the power gain is very
high as its output impedance is much lower than its input impedance. If a voltage gain greater
than one is required we can use the following filter circuit.
Page 4 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig. Frequency Response
OBSERVATION TABLE:
Sr.no Input frequency (HZ)
Vout
Vout /Vin =Gain
Gain (db) =20log Vout/Vin
FOR DIFFERENT CUTOFF FREQUENCY:
Resistance(Ω)
Capacitance (µF)
FH high cutoff
Frequency(HZ)
Page 5 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Procedure: 1. 1. Connect patch cords according circuit diagram as mentioned in kit trainer.
2. Connect +12V and -12V DC power supplies at there indicated position from external
source.
3. Switch ON the power supply.
4. Connect a sinusoidal signal of amplitude 1V (p-p) of frequency 1 KHz to the test point
Vin of this filter from external source.
5. Observe output on oscilloscope by connecting test point Vout to oscilloscope.
6. Increase the frequency of input signal step by step and observe the effect on output
Vout on oscilloscope.
7. Draw a graph between gain and frequency on graph paper.
Calculation: THEORETICAL CALCULATIONS:
Calculation all the following values
1.
2.
3.
4.
5.
6.
Pass band gain of low pass filter AF=1+RF/Rl
Pass band gain (db) =20log Vout/Vin
3 db frequency fH =1/2 πRC
gain at 3db frequency fH=0.707*AF
gain (db) at 3 db frequency fH= 20log Vout/ Vin where Vout =(2)1/2*Vin
Roll off rate = -20db /decade
Results: -
Page 6 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Theoretical
Practical
Pass band gain (Af)
Pass band gain (Af) in db
3 db frequency fH
Gain at 3 db frequency (fH)
in db
Each section and block will be studied by the students. And submitted in their lab session
Precautions:1. Connect the patch cord properly.
2. Power cable plugged properly.
3. Adjust the CRO for tracing the different Waveform.
4. Check the connection before starting the kit.
Lab Quiz:1. What is filter?
2. What is the function of low pass filter?
3. Why filter is necessary in communication?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
Page 7 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 8 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.02
First order high pass filter
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 9 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: For first order high pass filter evaluate
1. Lower cut off frequency
2. Pass band gain
3. Plot the frequency response of high pass filter.
Apparatus: 1. Bread board
2.
3.
4.
5.
6.
DC power supply ±12V
Function generator
Oscilloscope
multimeter
patch cords
Theory: An active filter is frequency selective circuit that passes electric signals of specific band of
frequencies and attenuates signal of frequencies outside this band. depending on the type of
elements used in their construction filters may be classified as passive or active filters. Elements
used in passive filters are resistors, capacitors and inductors.
Active filter consists of active components such as op-amp, transistors with passive
elements.
Most commonly used filters are:
A. Low pass filter
B. High pass filter
C. Band pass filter
HIGH PASS FILTER:
Page 10 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
It is a frequency selective circuit, which passes signals of frequencies above it s low cut
off frequency (fL) and attenuates signals of frequencies below fL.
Equation of high pass filter is
Vout /Vin =AF /1+J(f/fL)
……..1
Vout / Vin = AF / {1+(f/fL)2}1/2
………….2
Vin = Input signal voltage
Vout = output signal voltage
Vout / Vin = Gain of filter as a function of frequency
AF = 1+RF /R1 pass band gain of filter
F = frequency of input signal
fL = 1/2πRC = Low cutoff frequency, 3-db frequency, cornet frequency operation of high pass
filter using equation.
a.
at low frequencies f<fL
Vout / Vin
<AF
b.
at f = fL
Vout /Vin
=0.707*AF(approx.)
c.
at f>fL
Vout / Vin
=AF
In ideal high pass filter when f<fL gain is increased at a constant rate has a constant rate with an
increase in frequency, at fL the gain is 0.707*AF. And above fL it has constant gain of AF Below
fL when input frequency is increased tenfold (one decade), the voltage gain is multiplied 10.
Gain (db) = 20 log Vout /Vini.e. Gain Roll off rate is -20db/decade.
Using analysis techniques similar to those used for the low pass filter, it can be shown that
Page 11 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
which is the general form for first-order (one reactive element) low-pass filters. At high
o) the capacitor acts as a short, so the gain of the amplifier goes to H 0= R1/R2.
o) the capacitor is an open and the gain of the circuit is H o.
0=1/R2C. Therefore this circuit is a high-pass filter (it passes high frequency
signals, and blocks low frequency signals.
Page 12 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
OBSERVATION TABLE:
Sr.no Input frequency (HZ)
Vout
Vout /Vin =Gain
Gain (db) =20log Vout/Vin
FOR DIFFERENT CUTOFF FREQUENCY:
Resistance(Ω)
Capacitance (µF)
FL Lower cutoff
Frequency(HZ)
Procedure: 8. Connect patch cords according circuit diagram as mentioned in kit trainer.
9. Connect +12V and -12V DC power supplies at there indicated position from external
source.
10. Switch ON the power supply.
11. Connect a sinusoidal signal of amplitude 1V (p-p) of frequency 1 KHz to the test point
Vin of this filter from external source.
12. Observe output on oscilloscope by connecting test point Vout to oscilloscope.
13. Increase the frequency of input signal step by step and observe the effect on output
Vout on oscilloscope.
14. Draw a graph between gain and frequency on graph paper.
Page 13 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Calculation: THEORETICAL CALCULATIONS:
Calculation all the following values
7. Pass band gain of low pass filter AF=1+RF/Rl
8. Pass band gain (db) =20log Vout/Vin
9. 3 db frequency fL =1/2 πRC
10. gain at 3db frequency fL=0.707*AF
11. gain (db) at 3 db frequency fL= 20log Vout/ Vin where Vout =(2)1/2*Vin
12. Roll off rate = -20db /decade
Results: Theoretical
Practical
Pass band gain (Af)
Pass band gain (Af) in db
3 db frequency fL
Gain at 3 db frequency (fL)
in db
Each section and block will be studied by the students. And submitted in their lab
session
Precautions:-
5. Connect the patch cord properly.
Page 14 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
6. Power cable plugged properly.
7. Adjust the CRO for tracing the different Waveform.
8. Check the connection before starting the kit.
Lab Quiz:1. What is filter?
2. What is the function of high pass filter?
3. Why filter is necessary in communication?
Book: Lab experiment related theory available in following books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 15 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.03
Second order high pass filter
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 16 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: - To design second order low pass active filter.
Apparatus: 7. Bread board
8. DC power supply ±12V
9. Function generator
10. Oscilloscope
11. multimeter
12. patch cords
Theory: Second Order Low-pass Filter
Second order filters are important because higher order filters can be designed using them.
There are two topologies for a second order low pass filter, the Sallen-Key and the Multiple
Feedback ( MFB) topology.
The second order response provides a high frequency asymptotic slope twice as steep as the
first order.
The unity gain topology of the Sallen-Key is usually applied in filter designs with high gain
accuracy, unity gain, and low Q (less than 3).
Second Order Low-pass Filter
Second order filters are important because higher order filters can be designed using them.
There are two topologies for a second order low pass filter, the Sallen-Key and the Multiple
Feedback ( MFB) topology.
The second order response provides a high frequency asymptotic slope twice as steep as the
first order.
Page 17 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
The unity gain topology of the Sallen-Key is usually applied in filter designs with high gain
accuracy, unity gain, and low Q (less than 3).
1. The transfer function of the general Sallen-Key Low-pass filter is
1. For a unity gain circuit the transfer function simplifies to
1. The coefficients of the transfer function are
Page 18 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
1. In order to obtain real values under the square root, C2 must satisfy the following
condition
1. Given C1 and C2, the resistor values R1 and R2 are calculated through
A stop band response begin having a 40db /decaderace off is obtained with second order low
pass filter a first order 1pf can be converted in to a second order type simply by using an
additionae RC n/w.
Second order filter are additionae important because the higher order filter can be designed
using them the gain of the second order filter is set by R1 and RF while the high cut off
frequency FH is determined by R2;C2;R3 and C3 as follows.
FH = ½
For the deviation of FH
FURTHEN more for a SLP butter worth response the voltage gain magnitude.
CIRCUIT DIAGRAM:
Page 19 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
FILTER DESIGN : Expect for having the roll off rate in the stop band the frequency response of
the SLP is identical to that of first order type these fore the design steps of the second order
filter are identical to those of first order filter as follows.
1. Chose a value for high cut off frequency FH.
2. To simply the design calculation set R2 =R3 =R and C2=C3=C then choose a value of C<
1uf.
3. Calculated the value of R using eqn.
4. Finally because of the equal resistor (R2=R3) and capacitor (C2=C3) values. The pass
band voltage gain is AF=(1+RF/R1) of the second order LPF has to be equal to 1.586 RL
this gain is necessary to guarantee butter worth response since choose values of
R1<100Kohm and calculate the value of RF.
Procedure: 15. Connect patch cords according circuit diagram as mentioned in kit trainer.
16. Connect +12V and -12V DC power supplies at there indicated position from external
source.
17. Switch ON the power supply.
18. Connect a sinusoidal signal of amplitude 1V (p-p) of frequency 1 KHz to the test point
Vin of this filter from external source.
19. Observe output on oscilloscope by connecting test point Vout to oscilloscope.
20. Increase the frequency of input signal step by step and observe the effect on output
Vout on oscilloscope.
21. Draw a graph between gain and frequency on graph paper.
Page 20 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Calculation: THEORETICAL CALCULATIONS:
Calculation all the following values
13. Pass band gain of low pass filter AF=1+RF/Rl
14. Pass band gain (db) =20log Vout/Vin
15. 3 db frequency fL =1/2 πRC
16. gain at 3db frequency fL=0.707*AF
17. gain (db) at 3 db frequency fL= 20log Vout/ Vin where Vout =(2)1/2*Vin
18. Roll off rate = -20db /decade
Results: Design and analysed the frequency response of second order low pass filter.
Precautions:1. Connect the patch cord properly.
2. Power cable plugged properly.
3. Adjust the CRO for tracing the different Waveform.
4. Check the connection before starting the kit.
Lab Quiz:1. What is filter?
2. What do you mean by order of the filter?
2. What is the function of high pass filter?
3. Why filter is necessary in communication?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
Page 21 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 22 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.04
Second order high pass filter
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 23 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: For second order high pass filter evaluate
4. Lower cut-off frequency
5. Pass band gain
6. Plot the frequency response of high pass filter.
Apparatus: 13. Bread board
14. DC power supply ±12V
15. Function generator
16. Oscilloscope
17. multimeter
18. patch cords
Theory: As with the passive filter, a first-order high pass active filter can be converted into a secondorder high pass filter simply by using an additional RC network in the input path. The frequency
response of the second-order high pass filter is identical to that of the first-order type except
that the stop band roll-off will be twice the first-order filters at 40dB/decade (12dB/octave).
Therefore, the design steps required of the second-order active high pass filter are the same.
Second-order Active High Pass Filter Circuit
Page 24 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Higher-order high pass filters, such as third, fourth, fifth, etc are formed simply by cascading
together first and second-order filters. For example, a third order high pass filter is formed by
cascading in series first and second order filters, a fourth-order high pass filter by cascading two
second-order filters together and so on. Then an Active High Pass Filter with an even order
number will consist of only second-order filters, while an odd order number will start with a
first-order filter at the beginning as shown.
A second order high pass filter is obtained from a second LPF if R and C are interchanged and so
on i.e. by simply interchanged frequency determined resistor and capacitor.
The voltage gain magnitude eq. of the second order HPF is as follows
Where
Af =1.586 = pass band gain for the second order butter worth filter
F = frequency of the i/p signal
FL = low cut off frequency
Since second order LPF and HPF are the same ckt. Expect that the position of resistor
and capacitor are interchanged the design & frequency scaling procedure.
Page 25 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
CIRCUIT DIAGRAM:
Procedure: 22. Connect patch cords according circuit diagram as mentioned in kit trainer.
23. Connect +12V and -12V DC power supplies at there indicated position from external
source.
24. Switch ON the power supply.
25. Connect a sinusoidal signal of amplitude 1V (p-p) of frequency 1 KHz to the test point
Vin of this filter from external source.
26. Observe output on oscilloscope by connecting test point Vout to oscilloscope.
27. Increase the frequency of input signal step by step and observe the effect on output
Vout on oscilloscope.
28. Draw a graph between gain and frequency on graph paper.
Calculation: THEORETICAL CALCULATIONS:
Calculation all the following values
19. Pass band gain of low pass filter AF=1+RF/Rl
20. Pass band gain (db) =20log Vout/Vin
21. 3 db frequency fL =1/2 πRC
Page 26 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
22. gain at 3db frequency fL=0.707*AF
23. gain (db) at 3 db frequency fL= 20log Vout/ Vin where Vout =(2)1/2*Vin
24. Roll off rate = -20db /decade
Results: Designed & analysed the frequency response second order high pass filter.
Precautions:9. Connect the patch cord properly.
10. Power cable plugged properly.
11. Adjust the CRO for tracing the different Waveform.
12. Check the connection before starting the kit.
Lab Quiz:3. What is filter?
4. What do you mean by order of the filter?
2. What is the function of high pass filter?
3. Why filter is necessary in communication?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 27 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.05
Characteristics of a Line
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 28 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: -Measuring the characteristics of a line
Apparatus: 19. Bread board
20. Transmission Line Trainer Kit ST2266
21. DC power supply ±12V
22. Function generator
23. Oscilloscope
24. Multimeter
25. Patch cords
Theory: Characteristic of a shielded line : The coaxial lines used for the transmission of electromagnetic
waves consist of an external conductor of cylindrical shape, with an inner conductor arranged
along the axis of the former. The two conductors are separated by dielectric material of suitable
features.
One of the advantages of this kind of lines is that these lines are intrinsically self shielding, due
to the geometry of the arrangement of the two conductors. Moreover the shielding features of the
coaxial lines improve when the frequency increases.
From the electric point of view, a coaxial line can be considered as a cascade of line trunks. Each
one of them can be represented as being composed of resistive, inductive and capacitive circuit
elements of concentrated kind, as shown in the figure 1.
R = Ohmic resistance for unit length (100m in this trainer)
L = Inductance for unit length
G = Conductance for unit length
C = Capacitance for unit length
The transmission characteristics of a line are described in terms of propagation. constant g and of
characteristic impedance Z0. These parameters are typical values for each single line. The same
is true for the capacitance, the inductance, the resistance and the conductance for length unit. In
the telecommunications field, these values are generally expressed per meter or kilometer, for
Page 29 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
practical reasons. In this case, the symbol used to indicate these magnitudes are the common
symbols.
This experiment measures the characteristic parameters such as R, L, C, G, Z0 and r
for the transmission line included in this trainer.
Procedure: 1. Figure 1 shows the modalities for the measurement to be performed.
2. Make connections as in figure 1.
3. Both the inductance and the ohmic resistance of the line are measured in series
by short-circuiting end of the line and connecting the measuring instruments to
the start of the line. The capacitance and the conductance are measured in
parallel by operating on the open line.
4. The resistance R and the conductance G can be measured with an ohmmeter or
DMM. For the conductance to be measured an ohmmeter is required which is
able to perform resistance measurements with a range greater than 100 M.
5. For the measurement of series inductance L and the parallel capacitance C, a
LCR meter or measuring bridge is required. The results of these measurements
give values of R, L, C and G referred to the cable length that, in our case, is of
100 meters.
Z0 can be measured by using the following formula:
Z0 = L /C
Alternate: If the LCRQ meter is not available this experiment can be performed as
Page 30 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig. 1
Page 31 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig. 2
Precautions:13. Connect the patch cord properly.
14. Power cable plugged properly.
15. Adjust the CRO for tracing the different Waveform.
Page 32 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
16. Check the connection before starting the kit.
Lab Quiz:1. What is Tx. Line?
2. What is characteristics impedance?
3. Name the distributed parameters of a TX. line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 33 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.06
Attenuation of a Line
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Page 34 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Name of Technical Assistant:
Objective: - Measuring the Attenuation of a Line
Apparatus: 26. Bread board
27. Transmission Line Trainer Kit ST2266
28. DC power supply ±12V
29. Function generator
30. Oscilloscope
31. Multimeter
32. Patch cords
Theory: The ohmic resistance R & the conductance G are responsible for energy disspation in
the form of heat. These losses, which determine the attenuation characteristics, are
expressed in terms of “attenuation” “a” and can be calculated by :
a = 20 log (V2 / V1)
Where V1 = amplitude of signal at input
V2 = amplitude of signal at output
a = attenuation for given length
In this experiment we will measure the attenuation for the different trunks of
transmission line available on the trainer. See Figure 1
Page 35 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig.1
Concept of matched line :
Though the concept of match line is not treated in detail in this manual but the subject
is certainly known to the students from the theoretical course. We have already found
short-circuited resistance of the line when measured with Digital Multimeter is shown
Ω. For optimum
power transfer we should have the source resistance and terminating resistance also as
Ω.
the generator to match the line. For this purpose, it is recommended that the student
utilized for all the experiments wherever terminated line experiment is done.
Procedure: 1. Adjust Ri and RL for 18 and 68 respectively with the help of DMM.
2. Make connections as shown in figure 9.
3. Set the sine-wave frequency to approximately 100 KHz and level to 0.4 V.
4. Oscilloscope CH 1 shows applied input CH 2 shows outputs.
5. Measure signal level at Input, and at 25, 50, 75, and 100 m lengths.
6. Tabulate as under :
Length (m)
25
50
75
100
V1 (input)
V2 (output)
Page 36 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
7. Now, calculate the attenuations in dB at various lengths by the formula given
below : a = 20 Log V2 / V1
8. The attenuation is approximately -2 dB at 100 m.
9. Try the same with open-ended line and short-ended line.
Fig. 2
Page 37 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Precautions:17. Connect the patch cord properly.
18. Power cable plugged properly.
19. Adjust the CRO for tracing the different Waveform.
20. Check the connection before starting the kit.
Lab Quiz:1. What is VSWR?
2. What is characteristics impedance?
3. Name the distributed parameters of a TX. line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 38 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.07
Input Impedance of a Line
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Page 39 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Name of Technical Assistant:
Objective: - Measuring the Input Impedance of a Line
Apparatus: 33. Bread board
34. Transmission Line Trainer Kit ST2266
35. DC power supply ±12V
36. Function generator
37. Oscilloscope
38. Multimeter
39. Patch cords
Theory: The input impedance of the line depends on features like the ohmic resistance, the
conductance, the inductance and the capacitance. It is also related to the resistance
that loads the line at the opposite end and to both the frequency and voltage of the
signal. The purpose of the first part of the test is to measure the input impedance of
the line under different load conditions :
1. Line terminated with matched load
2. Open line
3. Short-circuited line.
In the second part of the test we will measure the phase displacement between the
input voltage and current, under the 3 conditions of line termination. When the
modulus and the phase displacement are known the impedance vector is fully
identified. See figure
Page 40 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
.
Fig. 1
Procedure: 1.
2. Make the connections as shown in figure 2.
3.
shown, in figure 12 allows to measure the value of input current.
4. Set the input at 0.4p-p and freq 100 KHz of sine-wave (both measurement on
CRO).
5.
6. Calculate the input impedance according to the following formula :
Zin = Vin / I
7. Change the frequency to 1MHz and note the values of Vin and Vm at this
frequency.
8.
Repeat the experiment with shorted and open line and use the following formulas to
Page 41 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Precautions:21. Connect the patch cord properly.
22. Power cable plugged properly.
23. Adjust the CRO for tracing the different Waveform.
Page 42 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
24. Check the connection before starting the kit.
Lab Quiz:1. What is reflection coefficient?
2. What is characteristics impedance?
3. Name the distributed parameters of a Tx. line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 43 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.08
Study of Stationary Waves
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 44 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: - Study of Stationary Waves
Apparatus: 40. Bread board
41. Transmission Line Trainer Kit ST2266
42. DC power supply ±12V
43. Function generator
44. Oscilloscope
45. Multimeter
46. Patch cords
Theory: A line that has not been terminated with a load equal to its characteristic impedance is
subject to a reflection phenomenon of the power from the remote end. The amount of
the reflected power depends on the amount of mismatch between the characteristic
impedance of the line and the load impedance. In the extreme cases of short-circuited
line (RL = 18Ω) and open line (RL = 68Ω) a situation of total reflection occur for either the
current wave or the voltage wave. The purpose of this test is to study the
establishment of the stationary waves within the line.
Procedure: 1. Ri and RL for 18 Ω and 68 Ω
2. Make connections as shown in figure 2
3. Set oscilloscope to 0.1 V / div for both channels.
4. Adjust the sine generator for an output of 0.2 Vp-p (2 div Deflection on CH 1)
and at frequency 100 KHz.
5. Observe the peak to peak voltages on CH 2 at 100 m and at intermediate sockets
at 75 m, 50 m & 25 m and 0m.
6. Tabulate results as under :
Distance
Vp-p
0m
25 m
Page 45 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
50 m
75 m
100 m
7. Calculate the stationary wave ratio ‘s’ by the following formula :
s = V max / V min
For 100 KHz‘s’ is approximately 1.25
8. The reflection coefficient ‘r’ of the line shows how much of the energy supplied
at the input is being reflected as a consequence of the load decoupling. The
reflection coefficient is normally expressed in percentage and can be determined
from the stationary wave ratio through the following formula :
r = (s - 1) / (s + 1)
At 100 KHz ‘r’ is approximately 11%
9. Repeat the same procedure for open line & short-circuited line.
10. Try the experiment with other frequencies to see the effect of frequency on 's'.
Fig.1
Page 46 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig. 2
Precautions:25. Connect the patch cord properly.
26. Power cable plugged properly.
27. Adjust the CRO for tracing the different Waveform.
Page 47 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
28. Check the connection before starting the kit.
Lab Quiz:1. What is a Tx. Line?
2. What is characteristics impedance?
3. Name the distributed parameters of a TX. line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 48 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.09
Fault localization within the line
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Name of Technical Assistant:
Page 49 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Objective: - Fault localization within the line
Apparatus: 47.
48.
49.
50.
51.
52.
53.
Bread board
Transmission Line Trainer Kit ST2266
DC power supply ±12V
Function generator
Oscilloscope
Multimeter
Patch cords
Theory: The Localization of the faults within the line can be performed following different methods. The
method shown here for performing this test is of special interest, being based upon the use of the
phenomenon of the establishment of stationary waves. Let's assume that the line is broken at
unknown point between two ends. If the line is connected to a signal generator, the wave will be
reflected from the break point, and a stationary wave condition is established between the input
and the breakpoint. The waves along the line have maximum and minimum points at regular
intervals corresponding to ¼ of the wave - length of the input signal. For the fault to be
pinpointed, it is necessary to determine, the frequency value at which a voltage minimum occurs
at the input. This frequency is noted as f1. The same operation is repeated at the remote end, of
broken cable, and obtaining f2 value. These values are substituted in the following formula :
l’ = [f2 / (f1 + f2)] / l
Where,
l = line length in meters
l’ = distance in mts of the point of fault referred to the input of the line.
Procedure: 1.Make connections as shown in figure 20 a. Note that the line is broken at 50 m
length.
Page 50 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
2. Set oscilloscope channel 1 to 0.1 V/ div.
3. Adjust the sine generator for output of 0.4 Vp-p (4 div deflection on CH 1)
4. Keep the frequency variable control at the minimum position.
5. Gradually increase the frequency and note the frequency at which the signal on
CRO falls to minimum. This frequency is f1.
6. Repeat the test at the other end of the line as shown in figure 20 b and note the
frequency at which signal on CRO falls to minimum. This is f2.
7. Enter these values in the formula and calculate the distance of break point from
the input.
For the fault generated at 50 m f1 and f2 are 900 KHz approximately.
Fig.1
Page 51 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig.2
Precautions:29. Connect the patch cord properly.
Page 52 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
30. Power cable plugged properly.
31. Adjust the CRO for tracing the different Waveform.
32. Check the connection before starting the kit.
Lab Quiz:1. What is a Tx. Line?
2. What is characteristics impedance?
3. Name the distributed parameters of a TX. line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 53 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
EXPERIMENT NO.10
Phase displacement between the current & voltage
Date of conduction:-
Date of submission:-
Submitted by other members:1.
2.
3.
4.
5.
6.
7.
8.
Group no:-
Signature
Name of faculty incharge:
Page 54 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Name of Technical Assistant:
Objective: -Phase displacement between the current & voltage at input of line
Apparatus: 54.
55.
56.
57.
58.
59.
60.
Bread board
Transmission Line Trainer Kit ST2266
DC power supply ±12V
Function generator
Oscilloscope
Multimeter
Patch cords
Theory: The phase displacement between the current & voltage at input of line, under the
different load conditions viz. matched line, open line and short-circuited line. See
figure.
Procedure: -
Page 55 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
1. Adjust Ri and RL for 18 Ω
Ω respectively with the help of DMM.
2. Make the connections as shown in figure 2.
3. A1 resistance in series between the generator and the transmission line as
shown, in figure 12 allows measuring the value of input current.
4. Set sine wave frequency to 100 KHz (use CRO).
5. Set the oscilloscope to XY mode.
6.
7. Observe suitable Lissajous pattern on CRO by adjusting V / div of each channel.
8. The Lissajous pattern allows measuring the phase displacement between the two
signals through the ratio of the semi axis of the ellipse.
Fig.1
Page 56 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Fig. 2
Page 57 of 58
NAME OF LABORATORY: CNTL
LAB SUBJECT CODE: EC-505
NAME OF DEPARTMENT: ELECTRONICS AND COMMUNICATION
Precautions:33. Connect the patch cord properly.
34. Power cable plugged properly.
35. Adjust the CRO for tracing the different Waveform.
36. Check the connection before starting the kit.
Lab Quiz:1. What is a Tx. Line?
2. What is characteristics impedance?
3. Name the distributed parameters of a TX. Line?
Book: Lab experiment related theory available in following
books:
1. Ryder: Networks and Transmission Lines, PHI Learning.
2. Valkenberg: Introduction to Modern Network synthesis, Wiley India.
3. Suresh: Electric Circuits and Networks, Pearson Education.
4. Raju: Electromagnetic field theory and Transmission Lines, Pearson Education.
5. Ganesan: Transmission Lines and Waveguides, TMH.
6. Rao: Electromagnetic Waves and Transmission Lines, PHI learning.
Page 58 of 58