## December 17, 2011

### ELECTRONIC MEASUREMENTS AND INSTRUMENTATION JNTU previous years question papers

ELECTRONIC MEASUREMENTS AND INSTRUMENTATION JNTU previous years question papers

Time: 3 hours Max Marks: 80
All Questions carry equal marks
1. (a) Explain the functioning of a potentiometer type digital voltmeter.
(b) A 31 2 digit of DVM has an accuracy of ± 0.5 percent of reading ± 1 digit.
i. What is the possible error in volt, when the instrument is reading 5.00 V on the 10 V range?
ii. What is the possible error in volt, when reading 0.1 V on the 10 V range?
[8+8]
2. (a) What is the need for inserting isolation between the signal generator output and oscillator in a simple signal generator? What are the different ways in which this can be achieved?
(b) With the help of a block diagram, explain the working of laboratory type pulse generator. [8+8]
3. (a) Draw and discuss the spectral displays of various modulations using Spectrum analyzer.
(b) Explain one application of distortion factor meter. [8+8]
4. (a) With a neat block diagram, explain the function of each block of a general purpose oscilloscope.
(b) Mention the advantages of general purpose oscilloscope. [10+6]
5. (a) With a suitable block diagram and waveforms, explain the operation of a frequency counter.
(b) How many displays (total decades) should a frequency counter have if its accuracy and resolution are to be 0.001 percent? [10+6]
6. (a) Explain the “parallel-connection” method of using Q-meter and Obtain the expressions for resistance, reactance and Q factor.
(b) Give the list of the detectors used in ac bridges. [10+6]
7. (a) What parameters should be considered in selecting a transducer?
(b) Define active transducer and passive transducer? Give the examples for each?
[8+8]
8. (a) With a neat sketch, briefly explain the principle of operation and force measurement by cantilever beam type load cell?(b) Explain the working of D.C. Tachogenerators with a neat sketch. What are its advantages and limitations?

## Government jobs in india 