MCQGeeks
0 : 0 : 1
CBSE
JEE
NTSE
NEET
English
UK Quiz
Quiz
Driving Test
Practice
Games
Quiz
Electrical Engineering
Microwave Communication
Quiz 2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Q.1
A thin layer of dirt and grime coverts the reflecting surface of the parabolic dish of a radar set. The particular effect on the performance of the radar will be
A decrease in range
A reduction in horizontal resolution
No noticeable effect
A decrease in gain
Q.2
A reflex klystron is oscillating at the frequency of its resonant cavity. If the reflector voltage is made slightly less negative, the
Oscillation will cease
Output power would increase
The frequency will decrease
Bunching would occur earlier in time
Q.3
At what position is the input signal inserted into a traveling-wave tube?
At the cathode end of the helix
At the collector
At the collector end of the helix
At the control grid of the electron gun
Q.4
The frequency of the oscillation generated by a magnetron, is mainly determined by
The flux density of the external magnet
The ratio of the dc cathode voltage to the magnetic flux density
The number of the cavity resonators
The dimension of each cavity resonator
Q.5
When used in conjunction with a radar set, the purpose of an echo box is to provide an artificial target.
Which may be used to tune the radar synchronizer
Which may be used to tune the radar receiver
To the tone of the pulse repetition
Tune the magnetron to the correct frequency
Q.6
Which of the following is used as an oscillator device in the SHF band?
Thyratron tube
Tunnel diode
Klystron tube
Both B and C
Q.7
Which of the following is used as a high power microwave oscillator?
Thyratron
Magnetron
Klystron
Reflex-klystron
Q.8
__________ is the progressive decrease of signal strength with increasing distance.
Radiation
Attenuation
Modulation
Propagation
Q.9
Which of the following permits a microwave signal to travel in one direction with virtually no loss, but severely attenuates any signal attempting to travel in the reverse direction?
Isolator
Wave trap
Tunnel diode
Circulator
Q.10
The main frequency determining element of a klystron is
The repeller voltage
The accelerating voltage
Its resonant cavity
Its mode of operation
Q.11
As the electron beam moves through a klystron’s intercavity drift space
Frequency modulation at the input cavity creates velocity modulation at the output cavity
Velocity modulation at the input cavity creates density modulation at the output cavity
Density modulation at the input cavity creates velocity modulation at the output cavity
Phase modulation at the input cavity creates velocity modulation at the output cavity.
Q.12
The highest frequency which a conventional vacuum tube oscillator can generate is not limited by the
Electron transit time
Distributed lead inductance
Inter-electrode capacitance
Degree of emission from the cathode
Q.13
Which of the reception problems below that is not due to multipath?
Delayed spreading
Rayleigh fading
Random Doppler shift
Slow fading
Q.14
If the instantaneous RF potentials on the two sides of a magnetron cavity are of opposite polarity, the operation is in the
π mode
π/2 mode
2π mode
π/4 mode
Q.15
Oscillators of a klystron tube are maintained
By bunches of electrons passing the cavity grids
By plate-to-cathode feedback
By feedback between the accelerating grid and the repeller
By circulating bunches of electrons within the cavities.
Q.16
A shipboard equipment which measures the distance between the ship’s bottom and the ocean floor.
Fathometer
Echosounder
LORAN
SONAR
Q.17
Rainfall is an important factor for fading of radio waves at frequencies above
10 GHz
100 GHz
1 GHz
100 MHz
Q.18
The coarse frequency adjustment of a reflex klystron is accomplished by
The AFC system
Adjusting the flexible wall of the resonant cavity
An adjustment in the synchronizer
Varying the repeller voltage
Q.19
In a pulsed radar set, the function of the duplexer is to
Aid in calibrating the display unit
Prevent frequency drift in the klystron
Allow the transmitter and the receiver to operate from a common antenna
All of these
Q.20
A PPI cathode-ray tube as used on a radar set
Is used to check the percentage of modulation
Indicates both the range and azimuth of a target
Indicates only the range of a target
Is used for receiver alignment
0 h : 0 m : 1 s
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Report Question
×
What's an issue?
Question is wrong
Answer is wrong
Other Reason
Want to elaborate a bit more? (optional)
Support mcqgeeks.com by disabling your adblocker.
×
Please disable the adBlock and continue.
Thank you.
Reload page