JNTU Question Papers
Instrumentation Components 1st Nov 2008
1. (a) Distinguish between pivots and bearings. Write down the advantages and
disadvantages of pivots and bearings. [4+4]
(b) Describe the different Basic Counting of Ratchets. Give its uses. 
2. (a) What are the basic requirements of control mechanism?
(b) With a block schematic the functioning of a control mechanism. [8+8]
3. (a) What is the difference between a switch and a relay? 
(b) Explain the working of a electromechanical relay with a neat sketch and give
the applications. [4+4+4]
4. (a) Sketch the block diagram of a servo system using two phase motor and derive
its transter function. [4+4]
(b) What will be the response of the system for step input. 
5. (a) Draw the input and output characteristics of a CC npn transistor and show
different regions in it.
(b) Give the relations between current gains of CB and CE transistor configuration.
(c) Draw the circuit diagram of a CE transistor of configuration and explain its
using its characteristics. [8+2+6]
6. (a) Give the construction, equivalent circuit and characteristics of DIAC and explain its operation.
(b) Sketch SCR phase control circuits for
i. 90 degrees phase control
ii. 180 degrees phase control.
In each case show the load waveform and explain the operation of the circuit.
7. (a) What is the essential difference between principle of operation of normal p-n
diode and a LED.
(b) Describe the working principle of light emitting diode with neat diagram.
(c) Draw the schematic representation of an optocoupler and explain its working
8. (a) Discuss the spectral transmittance characteristics of an absorption filter.
(b) What are the parameters to be observed in the design of grating.
(c) Give two types of mounting of grating and explain the importance of mount
in the grating. [6+4+6]