A-006-05: Performance limitations - instability, image, spurious, etc.
A-006-05-01:
What part of a superheterodyne receiver determines the image rejection ratio of the receiver?
RF amplifier
Product detector
AGC loop
IF filter
A-006-05-02:
What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?
Desensitization
Cross-modulation interference
Squelch gain rollback
Quieting
A-006-05-03:
What causes receiver desensitization?
Strong adjacent channel signals
Squelch gain adjusted too high
Squelch gain adjusted too low
Audio gain adjusted too low
A-006-05-04:
What is one way receiver desensitization can be reduced?
Shield the receiver from the transmitter causing the problem
Decrease the receiver squelch gain
Increase the receiver bandwidth
Increase the transmitter audio gain
A-006-05-05:
What causes intermodulation in an electronic circuit?
Nonlinear circuits or devices
Too little gain
Positive feedback
Lack of neutralization
A-006-05-06:
Which of the following is an important reason for using a VHF intermediate frequency in an HF receiver?
To move the image response far away from the filter passband
To provide a greater tuning range
To tune out cross-modulation distortion
To prevent the generation of spurious mixer products
A-006-05-07:
Intermodulation distortion is produced by:
the mixing of more than one signal in the mixer of a superheterodyne receiver
the interaction of products from high-powered transmitters in the area
the high-voltage stages in the final amplifier of an amplitude or frequency-modulated transmitter
the mixing of more than one signal in the first or second intermediate frequency amplifiers of a receiver
A-006-05-08:
Three of the following answers are direct causes of instability in a receiver. Choose the answer which is NOT a direct cause:
dial tracking
mechanical strength
feedback components
temperature
A-006-05-09:
Poor stability in a receiver usually originates in the:
local oscillator and power supply
detector
RF amplifier
mixer
A-006-05-10:
Poor dynamic range of a receiver can cause many problems when a strong signal appears within the front-end bandpass or even outside it. Which of the following is NOT caused as a direct result?
Feedback
Desensitization
Intermodulation
Cross-modulation
A-006-05-11:
If a receiver mixes a 13.800-MHz VFO with a 14.255-MHz received signal to produce a 455-kHz intermediate frequency (IF) signal, what type of interference will a 13.345-MHz signal produce in the receiver?
Image response
Intermediate interference
Mixer interference
Local oscillator
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● = Incorrect answer
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