20
3-29. Feedhorn shadows can be eliminated by
taking which of the following actions?
1. By making the horn smaller
2. By making the reflector smaller
3. By offsetting the horn from the
center of the reflector
4. By putting the horn behind the
reflector
3-30. Airborne radars have unique physical
design requirements. Which of the
following functions is performed by the
radome?
1. It serves as the antenna
2. It provides aerodynamic shape
3. It protects the antenna from low air
pressure
4. All of the above
3-31. If a fixed-frequency radar transmitter is
found to be off its normal operating
band, which of the following corrective
actions should be taken?
1. Retune the transmitter
2. Change the assigned frequency
3. Replace the defective part causing
the error
4. Check the frequency again, an error
has been made
3-32. If a transmitter carrier wave is modulated
by a square wave, what maximum
number of different frequencies will be
produced?
1. An infinite number
2.
2
3.
3
4.
4
3-33. Which of the following statements
describes a radar transmitter frequency
spectrum?
1. The distribution of energy over a
band of frequencies
2. The distribution of energy over time
3. The prf multiplied by the duty cycle
4. The pulse width versus peak power
3-34. What total number of modulating
components are present in the output
spectrum of a pulse radar transmitter?
1.
1
2.
2
3.
3
4.
4
3-35. An ideal radar frequency spectrum would
be best described in which of the
following ways?
1. It is symmetrical
2. It has a wide lobe
3. It has narrow side lobes
4. It has no minimum points
3-36. In a good spectrum curve the distance
between the two minima is proportional
to which of the following transmitter
parameters?
1. Prt
2. Prf
3. Peak power
4. Pulse width
3-37. The echo box is a good instrument for
measuring overall radar system
performance because it indicates the
combined effectiveness of which of the
following components?
1. Antenna and duplexer
2. Transmitter and antenna
3. Transmitter and receiver
4. Receiver and synchronizer
