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
Q.2
A reflex klystron is oscillating at the frequency of its resonant cavity. If the reflector voltage is made slightly less negative, the
Q.3
At what position is the input signal inserted into a traveling-wave tube?
Q.4
The frequency of the oscillation generated by a magnetron, is mainly determined by
Q.5
When used in conjunction with a radar set, the purpose of an echo box is to provide an artificial target.
Q.6
Which of the following is used as an oscillator device in the SHF band?
Q.7
Which of the following is used as a high power microwave oscillator?
Q.8
__________ is the progressive decrease of signal strength with increasing distance.
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?
Q.10
The main frequency determining element of a klystron is
Q.11
As the electron beam moves through a klystron’s intercavity drift space
Q.12
The highest frequency which a conventional vacuum tube oscillator can generate is not limited by the
Q.13
Which of the reception problems below that is not due to multipath?
Q.14
If the instantaneous RF potentials on the two sides of a magnetron cavity are of opposite polarity, the operation is in the
Q.15
Oscillators of a klystron tube are maintained
Q.16
A shipboard equipment which measures the distance between the ship’s bottom and the ocean floor.
Q.17
Rainfall is an important factor for fading of radio waves at frequencies above
Q.18
The coarse frequency adjustment of a reflex klystron is accomplished by
Q.19
In a pulsed radar set, the function of the duplexer is to
Q.20
A PPI cathode-ray tube as used on a radar set
0 h : 0 m : 1 s