8/12/2019 acs......................ecet

1/7

1. Compound with equivalent Han emission lines, 3 ghz move guides

a)are less Larry b)can carry higher power c)are less buly

d)have lower attenuation

!. a duple"er is used

a)to couple two di#erent antennas to a transmitter without mutual inter$aces

b)to allow the one antenna to be used $or reception or %" without mutual

inter$erence

c)to prevent inter$erence between two antennas when they are connected to a

receiver

d)to increase the speed o$ the pulsar in the pulsed &'('&

3.indicate which o$ the $ollowing cannot be $ollowed by the word waveguide*

a)elliptical b)+ecible c)coa"ial d)ridged

. in order to reduce cross sectional dimension, the wave guide is to use

a)circular b)ridged c)rectangular d)+e"ible

-.the primary purpose o$ the beli" in a traveling wave tube is to

a)prevent the electron beam $rom spreading in the long tube

b)reduce the a"ial velocity o$ the & /eld c)ensure broadband operation

d)reduce the noise /gure

0. a magnetron where oscillating $requency is electrically adustable over a wide

range is called a

a)coa"ial magnetron b)dither2 tuned c)$req. agil d)%4

5. the biggest advantages o$ the %&'6'%% diode over the 746'%% diode is its

a)low noise b)higher e8ciency c)ability to operate at higher $req.

d)lesser sensitivity harmonics

9. the biggest advantages o$ the $ollowing diodes will produces the pulsed in its

operation

a)varactor b):unn c)schotty carrier d)&746'%%

8/12/2019 acs......................ecet

2/7

;. indicate which o$ the $ollowing diodes does not use negative resistance in its

operation

a) bacward b):unn c)746'%% d)tunnel

1indicate the $alse answer)

a)$or electronic tunning b)$or $req. multiplication c)as an oscillator

d)as a parametric ampli/er

1!. negative resistance is obtained with a :unn diod because o$

a)electron trans$er to a less mobile energy level b)qualenche breadown

with high voltage sssgradient c)sssstunneling across the unction

d)sselectron domains $orming at the unction

13. $or :unn diodes , gallium arsenide is pre$erred to silicon because the $ormer

a)has a switched empty energy band,which silicon does not have b)shas

higher ion mobility c)shas a lower noise at the highest $rq. d)is capable o$

handling higher power densities

1.the biggest diadvantages o$ the 746'%% diode isits

a)lower e8ciency than that o$ the other microwave diode b)high noise

c)inability to provide operation d)low power handling ability

1-. the dominant mode is the one which is having

a)highest cuto# $req. b)lowest cuto# $req., c)lowest cuto# $req.

d)none

10. in a rectangular waveguide , the dominant made $or transverse electric

mode

a)%?1.1 b) %4 1,1 c) %?1,< d)none

15. an ?4 wave in space is

a) %? b) %4 c) %?4 d) none

19. an isolator is @@@@@@@@@@transmission device

8/12/2019 acs......................ecet

3/7

a)reciprocal b)non reciprocal c) a and b d)none

1;. 67A diode operates in

a)$orward bias b)reverse bias c)saturation d)cuto#

!

8/12/2019 acs......................ecet

4/7

1-. 10.C 15.C 19. 1;. !

8/12/2019 acs......................ecet

5/7

;. the resolution o$ a pulsed radar can be improved by

a)increasing pulse width b)decreasing pulse width c)increasing pulse amplitude

d)increasing 6&

-

8/12/2019 acs......................ecet

6/7

-;. the (oppler e#ects is in

a)moving target plotting on the 667 b)the 4%7 system c)4 C radar d)C

&'('&

0

8/12/2019 acs......................ecet

7/7

a)large ma"imum range b)good target discrimination c)di8cult

discrimination d)increased capture area

5