Electronic Instrumentation (EX-604 (A)) - Important Questions

Explain the principle, construction and working of dual-beam CRO and dual-trace CRO with neat sketch and contrast/compare them.

Draw the block diagram of a general purpose CRO and explain the function/working of each block/part, including applications of CRO.

Explain the construction and working of a dual-beam oscilloscope with neat diagram/sketch.

Write short note on multi-input sampling oscilloscope.

Explain the construction and working of time base circuits. How does sweep synchronization affect the accuracy of waveform display?

Discuss the role and significance of post-deflection acceleration in CRT-based CROs. How does it affect the beam velocity and spot size?

Illustrate electrostatic deflection in a CRT with a sketch and define deflection factor and deflection sensitivity.

List applications of sampling oscilloscope and precautions to be taken when using it.

Determine unknown frequency from Lissajous pattern tangency counts and known input frequency.

Describe the different types of graticules used in CRO.

Explain dual-beam CRO and sampling CRO with necessary sketches and diagrams.

Define graticule, Lissajous pattern, and Q meter.

Explain the circuit and working of the Wien bridge for measurement / determination of frequency.

Explain loss factor/dissipation factor of a capacitor, its relation to Q-factor, and the working of the Schering bridge (including high-voltage features) for measuring it.

Solve numerical problem on Maxwell bridge at balance to find series equivalent inductance and resistance of unknown inductive impedance.

Compare Schering bridge and De Sauty bridge for capacitance measurement in terms of frequency response and dielectric loss measurement.

Draw circuit diagram of Maxwell's inductance-capacitance bridge, derive balance equations for unknown inductance and resistance, and discuss merits and demerits.

Numerically determine unknown capacitances from balance condition of a Wien bridge at a given frequency.

Solve a balanced Schering bridge numerical to find the unknown capacitance and power factor/dielectric loss.

Why is Anderson loop proposed for impedance measurement? What is the basic circuit topology?

Name a few AC bridges used in practice and specify which bridge is used for measurement of what type of impedance?

Explain the suitability of Maxwell inductance-capacitance bridge for measuring inductance of coils with storage factor (Q) between 1 and 10.

Write a short note on any two of the following.

What are the sources of errors in bridge circuits? How they can be minimized? Explain.

Explain the working principle / theory of a resistance strain gauge (resistance change due to strain) and derive / define the expression for gauge factor.

Explain the construction and working of LVDT.

Write short notes on thermocouple and Hall effect transducers.

Differentiate between photo-voltaic, photo-conductive and photo-diode transducers. Which one is more suitable for low-intensity light detection and why?

Explain the concept of digital multiplexing in transducer interfacing. How does it improve system efficiency in industrial automation?

What is a transducer? Explain primary and secondary transducers with an example, including input characteristics.

Define strain gauge and compare gauge factor and temperature sensitivity of metal vs semiconductor resistance strain gauges.

Numerical on strain gauge: given gauge factor, strain and initial resistance, calculate percentage change in resistance.

Calculate force, charge and voltage for a piezo quartz crystal of given dimensions and properties under a given strain.

Define gauge factor and explain whether it depends only on electrical property or other properties.

Explain with circuit diagram how an instrumentation amplifier is adapted to a bridge circuit for measurement of strain.

Explain how Hall voltage is generated in a Hall device and the meaning of geometrical correction factor.

What is a function / signal generator? Explain its working principle / operation with block diagram, including how sine wave is produced.

Explain the circuits and working of frequency-selective (audio frequency) and heterodyne (megahertz range) wave analysers, including differences in sensitivity and selectivity.

Explain spectrum analysis and the operation of a spectrum analyser with block diagram.

Compare fixed-frequency and sweep frequency signal generators.

Draw the block diagram of a function generator and explain how its frequency is controlled by an external voltage input.

Explain the terms total harmonic distortion and beat frequency oscillator.

Discuss in detail the AF sine and square wave generator.

Describe with the help of a diagram the working of a beat frequency oscillator.

Explain the block diagram, working principle, operation and function of each block of a digital frequency meter.

Compare electrophoretic image display vs liquid vapour display, and analog recorders vs digital XY recorders

Explain the operation of a dual-slope integrating type digital voltmeter and compare it with successive-approximation type in terms of accuracy and speed.

Explain the role of RS232C and IEEE-488 (GPIB) interfaces in instrumentation and compare them with modern USB and Ethernet-based control.

Write short notes on instrumentation topics including GPIB electrical interface.

State the advantages of a digital voltmeter and explain the operating principle of a ramp-type DVM with diagram.

A 3½ digit voltmeter is used for voltage measurement.

Discuss the use of LED and LCD as display devices and compare their relative merits and demerits

Explain the IEEE-488 (GPIB) instrumentation bus with schematic diagram.

Define the terms LED and DVM.

What is XY recorder? Explain with suitable circuit diagram, the working of an XY recorder and also write its applications.

Explain the theory, working and advantages of LCDs