Dnyaneshwar Vidyapeeth (Trust)

Assignment 2

 

ASSIGNMENT  TELECOMMUNICATION ENGINEERING

SUB –CODE- (ETC-D570T)            COURSE:  TECH QUIC DIPLOMA          SESSION - SUMMER

                                                        BRANCH – E&TC

 

Q. 1)   Solve.

 

     1.  A PIN diode is

a)    a metal semiconductor point-contact diode

b)    a microwave mixer diode

c)     often used as microwave detector

d)    suitable for use as a microwave switch

2. The multi cavity klystron

a)   Is not good low level amplifier because of noise

b)   Has high repeller voltage to ensure rapid transit time

c)    Is not suitable for pulsed operation

d)   Needs long transit time through bunches cavity to ensure current   modulation

 

      3  . Define Antenna

  1. Define Directive gain
  2. Define Power gain

 

  1. Define Pedestal Height
  2. Indicate the antenna that is not wideband:
    1. Discone
    2. Folded dipole
    3. Helical
    4. Marconi

 

  1. One of the following is not an omnidirectional antenna :
    1. Half-wave dipole
    2. Log-periodic
    3. Discone
    4. Marconi

 

  1. The cavity magnetron uses strapping to
    1. prevent mode jumping
    2. prevent cathode back-heating
    3. ensure bunching
    4. improve the phase-focusing effect.

 

  1. The tunnel diode
    1. has a tiny hole through its center to facilitate tunneling
    2. is a point-contact diode with a very high reverse resistance
    3. uses a high doping level to provide narrow junction
    4. works by quantum tunneling exhibited by Gallium Arsenide only

 

  1. The negative resistance in a tunnel diode
    1. is maximum at the peak point of the characteristic
    2. is available between the peak and valley points
    3. is maximum at the valley point
    4. may be improved by the use of reverse bias

 

Q. 2) Solve.

 

  1. Give the applications of magnetron.
  2. Explain the process of bunching in case of magnetron
  3. Explain the concept of rectangular waveguide.
  4. Write a note on – Telephone conferencing
  5. What is call forwarding? How it is carried out?
  6. Explain different types of telephone exchange.

 

Q. 3) Solve.

 

  1. Explain step by step switching method in telephony
  2. Explain wire & wireless communication.
  3. What is radiation pattern of antenna?
  4. Compare fixed telephone and mobile telephone.
  5. Explain with schematic diagram operation reflex klystron
  6. Sketch a Gunn diode construction, and describe it briefly. What are some of the performance figures of which Gunn diodes are capable?
  7. Write a note on – Resonant Antennas

 

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