10-23.
At which of the following
frequencies is atmospheric static
most critical?
1.
500 kHz
2.
25 MHz
3.
50 MHZ
4.
500 MHz
10-24.
Precipitation static is a severe
problem in which of the following
frequency bands?
1.
Low only
2.
Medium only
3.
Low and medium
4.
Ultra high
10-25.
Cosmic noise is normally heard in
which of the following frequency
bands?
1.
Low only
2.
Medium only
3.
Low and medium
4.
Ultra high
10-26.
Which of the following is a
typical source of sustained
switching transients?
1.
Receivers
2.
Transmitters
3.
Synchronizers
4.
Generators
10-27.
Broadband random noise consists of
impulses that have which of the
following characteristics?
1.
Regular in shape and
recurrence rate
2.
Irregular in shape and
duration
3.
Constant in voltage and
duration only
4.
Constant in voltage, duration,
shape, and recurrence rate
10-28.
A circuit or device that carries a
varying electrical current is a
potential source of receiver
interference.
1.
True
2.
False
10-29.
What type of dc motor, if any, is
more apt to cause interference
(noise) in a radio receiver?
1.
Permanent magnet
2.
Series wound
3.
Shunt wound
4.
None
10-30.
The control circuit of a relay may
cause more interference than the
higher powered circuit being
controlled by the relay.
1.
True
2.
False
10-31.
Radio interference from operating
radar is most likely caused by
which of the following circuits?
1.
Indicator
2.
Modulator
3.
Receiver
4.
Synchronizer
10-32.
In the tuning band of a receiver,
oscillator leakage is the greatest
at which of the following points?
1.
Both the high and low ends
2.
The low end
3.
The middle range
4.
The high end
10-33.
If a receiver has an operating
frequency of 150 MHz and an IF of
20 MHz. what is the oscillator
leakage frequency?
1.
20 MHz or 150 MHz
2.
120 MHz or 150 MHz
3.
130 MHz or 170 MHz
4.
150 MHz or 170 MHz
10-34.
Radio interference is caused by a
cold-solder joint for which of the
following reasons?
1.
Its reactance varies with
applied voltage
2.
Its resistance varies with
applied voltage
3.
Its capacitance varies
inversely with frequency
4.
Its inductance varies with
frequency
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