Electronic Instrumentation December 2010

Note: Answer any FIVE full questions, selecting at least TWO questions from each part.

PART-A

1 a. State the three types of systematic errors giving examples for each.

b.  The current through a resistor is 2.5 A, but the measurement yields a value of 2.45 A. Calculate the absolute error, percentage error, relative accuracy and percentage accuracy.

c.  How is voltage in microvolts range measured? Explain with the help of a neat diagram. What is the use of chopper in micro voltmeter?

2  a. Differentiate between shunt type and series type ohm meter.

b.  A series ohm meter uses a 50 Q basic measurement requiring a full scale deflection of 1 mA. The internal battery voltage is 3 V. The desired scale marking for half scale deflection is 2000 Q. Calculate :

i)   Values of Ri and R2

ii) Maximum value of R2 to compensate 10% drop in battery.

c.   Explain with the help of a neat circuit diagram, the working of dual slope DVM.

d.  An integrator contains 100 KC2 and 1 |xf capacitor. If the applied voltage to the integrator input is 1 V, what voltage will be present at the output of integrator after 1 sec?

3 a. Explain the operation of digital millimeter.

b.  Explain with the help of a neat sketch, the working of digital frequency meter.

c.   Explain the operation of digital capacitance meter.

4 a. List specifications that should be considered while selecting a recording instrument.

b.   Explain the working of X – Y recorder.

c.   Describe applications of recording instruments.

d.  Explain the working of strip chart recorder.

PART-B

5  a. Draw a block diagram of a function generator. Explain the method of producing sine waves.

b.  Mention standard specifications of signal generator.

c.  List the various controls on the front panel of a pulse generator. Mention their uses.

6 a.Explain with the help of a neat diagram, the working of vector impedance meter.

b. How is field strength measured?

c. How can a Q-meter be used for the measurement of:

i)  D.C resistance of a circuit

ii) Stray capacitance.

7  a. On what principle does R-X meter operate? Explain.

b.   How can transistor tester be used for measurement of the following?

i) Faulty transistor

ii) Beta gain

c. What are the functions of transducer?

d.   List four types of electrical pressure transducer. Describe the application of each type.

8 a. Explain the operating principle of LVDT.

b.   Explain seven segment LED display.

c.    What are the advantages of LCD display over Nixie tube and LED display?

d.   What are the operating principles of LCD display?