MEPCO: Communication,electronics, DSP, control, microwave

We built control systems for _______

1. Power amplification 2. Remote control 3. Convenience of input form 4. Compensation for disturbances

Cross over distortion is problem in __________ class of amplifiers

Class B

Horizontal line in the s plane represents_______

Constant damping

digital multimeter is a combination of ?

DC voltmeter, AC voltmeter, ammeter, ohmmeter

Common mode rejection ratio is the ratio of

Differential mode gain to Common Mode gain

A digital signal is what in A. Dicrete B. Discrete in time C. Discrete in amplitude D. Discrete in neather time nor amplitude E. Discrete in both amplitude and time

Discrete in both amplitude and time

The channel of a JFET is between the A. Gate and drain B. Drain and source C. Gate and source D. Input and output

Drain and source

Kilowatt hour is the unit of (this was repeated two times)

Energy

Signal with different frequency and sampling rate are time division multiplexed by ________ a. FDM b. Synchronous Multiplexing c. Pulse Stiffing

FDM

The wavelength of an EM wave after reflection at an angle on a surface

Increases in the actual direction of propagation

Transfer function is A. Mathematical model B. System with no physical structure C. Can be calculated through differential equations

Mathematical model

Δ x H = J + D is?

Maxwell equation

Continuous signal in the time domain is ____ in frequency domain?

It is sum of infinite exponentials

fault analysis is done by ?

Jordan principle

For measuring small resistance we use

Kelvin bridge

A _____ meter is used a null detector in wheatstone bridge A. Ammeter B. Voltmeter C. Galvanometer

Voltmeter

bridge used for the measurement of resistance

Wheatstone bridge

A moving iron ammeter coil has few turns of thick wire in order to have: A. Low resistance B. High sentivity C. Effective damping D. Large scale

low resistance

Function of diode is__________

rectification

If pole is in left half of s plane system is.........

stable

What is zero in resonance circuit?

zeries(reactance)

_____acts as voltage controlled variable capacitor

Varactor

________ diode is used as voltage controlled capacitor.

Varactors

An Ideal voltage source has internal resistance

0Ω Resistance

What will be the sampling frequency that reveals the same sampled signal

2Fmax

When the current decreases to 2% the power in bulb decrease to______?

4%

In z transform cos pi/4 is the period is equal to

8pi

____ is defined as the measure of instrument by which it is error free A. Accuracy B. Precision C. Resolution

Accuracy

Which transistors are used in TTL?

Bjts ransistor-transistor logic (TTL) is a class of digital circuits built from bipolar junction transistors (BJT) and resistors. It is called transistor-transistor logic because both the logic gating function (e.g., AND) and the amplifying function are performed by transistors (contrast with resistor-transistor logic (RTL) and diode-transistor logic (DTL)).

DC to DC with high voltage gain ______

Boost (uses mosfet)

If poles and zeroes are within unit circle then A. System is stable B. Inverse of system is stable C. Both system and its inverse are unstable D. Both system and its inverse are stable

Both system and its inverse are stable

By connecting a shunt of higher value in ammeter __________ will decrease

Current sensitivity decreases

If ROC (Region of Convergence) does not converge then A. Z transform does not exist B. Fourier transform does not exist

Fourier transform does not exist

Main feature of crystal diode _________ a. Stability b. Reliability c. High frequency

High Frequency Crystal diode is also called as a Cat's-whisker diode or Point-contact diode or Crystals. These diodes microwave-semiconductor devices were developed during the World War II to be used in the microwave receivers and detectors.

In LTI system is characterized by A. Impulse input B. Step input

Impulse input

Hay bridge is used for the measurement of

Inductance

Superposition theorem relates to which system?

Linear system

The EM field and current are concentrated close to the surface of the conductor. The phenomenon is called?

Skin Effect

A diode that has a negative resistance characteristics is the A. Schottkey diode B. Tunnel diode C. Hot-carrier diode D. Laser diode E. Zener Diode

Tunnel diode

Output of system depends only on present or past value not on future value, then system is said to be

causal

in z transform, ROC is centred at____

origin

What is max in resonance ckt......

series (current)

Which type of system is referred by pneumatic system A. Pressure B. Hydraulic C. Fluid

Pressure

Electrical lines of force about a negative charge are? A. Circular, anticlockwise B. Circular, clockwise C. Radial, inward D. Radial, outward

Radial, inward

Due to voltage saturation, MOSFET enters in

Saturation region

Natural frequency in the control system represents

Transient response

fastest damping possible without overshoot in ____

criticaly damped system

If R1 is the resistance of a coil of copper at t oC and RT is the resistance at T oC and also the resistance temperature coefficient of copper per degree centrigrade at 0oC is 1/234.45, then Rt/RT (A) (1+t) / (1+T) (B) (1+ 234.45t) / (1+234.45 T) (C) (234.45 + t) / (234.45 + T) (D) (234.45 + t2 ) / (234.45 + T 2).

(234.45 + t) / (234.45 + T)

Modulation techniques in which carrier is switched between two different carrier levels _________

On/off keying

Resolution of ADC is defined as the no. of bits in_____

Output

An Ideal current source has internal resistance

∞Ω Resistance or open circuit