Amateur ExtraE4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

A
Answer
Receivers, transmitters, and measurements
Type
A
Spurious signals caused by cross modulation and desensitization from strong adjacent signals
B
Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C
Poor weak signal reception caused by insufficient local oscillator injection
D
Oscillator instability and severe audio distortion of all but the strongest received signals

Answer Notes

Dynamic range refers to the difference between the weakest signal a receiver can detect (the noise floor) and the strongest signal it can handle before overloading. A receiver with poor dynamic range struggles to process weak signals when strong signals are nearby on the band. When a receiver's dynamic range is exceeded by strong adjacent signals, its front-end amplifier or mixer becomes overloaded. This leads to issues like cross-modulation (where the voice or data of the interfering signal superimposes onto the desired signal) and desensitization (where the receiver's gain is pushed down, making the band sound dead). The distractors list internal hardware issues like oscillator instability, poor local oscillator injection, or general audio distortion. These are internal design flaws or drift problems, not consequences of external signal overload caused by poor dynamic range.
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What is meant by the blocking dynamic range of a receiver?
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What creates intermodulation interference between two repeaters in close proximity?