Paramjeet Singh Jamwal
Guru Nanak Education Trust Group Of Institutions
Roorkee – 247667, Uttarakhand, INDIA
PARAM SAMPLE PAPER
(SEM – III) PRE-UNIVERSITY EXAMINATION
ELECTRONIC MEASUREMENT & INSTRUMENTATION
Time: 3 Hours Total Marks: 100
Note: Attempt all questions.
Q1. Attempt any four parts: – (5×4=20)
a) With the help of a neat diagram explain the principle of a moving coil galvanometer. Discuss its applications.
b) How PMMC meter can be converted into an ammeter? Explain with circuit diagram.
c) Explain the use of shunt as a device for extending the range of ammeter. What are the advantages of shunt?
d) How PMMC instrument can be converted into a voltmeter? Explain with circuit diagram.
e) Explain the terms “accuracy”, “sensitivity”, and “resolution” as used for indicating instruments.
f) What are the instrumental, environmental, and observational errors? Briefly explain about each one of them.
Q2. Attempt any four parts: (5×4=20)
a) Explain the term “loading” in voltmeter and give the method to remove the adverse effect of loading.
b) Explain digital voltmeter with suitable diagram. Also write its merits and demerits in comparison to analog voltmeter.
c) Draw the block diagram of dual slope type digital voltmeter and explain its working.
d) A digit DVM has accuracy specification of ± 5 % of reading ± 1 digit. What is error in volts when reading is 5.00 V on its 10 V range?
e) Draw the circuit of a digital frequency meter.
f) Explain the difference between digit and 4 digit displays.
Q3. Attempt any two parts: (10×2=20)
a) Explain the operation of the single beam dual trace CRO. Also explain the use of this CRO in chop mode and in alternate mode. Sketch waveforms for illustration of the two modes of operation.
b) Explain the working of sampling oscilloscope with suitable diagram. Discuss the loading and measurement effects on CRO probes.
c) What is the function of a time base circuit in a CRO? Draw the basic circuit of an oscilloscope time base generator and explain its operation.
Q4. Attempt any two parts: (10×2=20)
a) Explain Wheatstone bridge and derive the expression bridge sensitivity.
b) Explain practical Q-meter with suitable diagram. Also mention various sources of errors in Q-meter.
c) Explain the operation of Capacitance Bridge in general with suitable neat diagram.
Q5. Attempt any two parts: (10×2=20)
a) Write short notes on X-Y recorders.
b) Write short note on ‘plotter’ or ‘voltage calibrator’.
c) Describe the different parts of CRT.