Deep Dive: E7E03
The correct answer is D: A circuit for detecting FM signals. What is a frequency discriminator is a circuit for detecting FM signals. Frequency discriminators demodulate FM signals. For amateur radio operators, this is important for demodulation. Understanding this helps when working with FM receivers.
Why Other Answers Are Wrong
Option A (FM generator circuit): Incorrect. FM generator isn't discriminator - discriminator detects FM signals. FM generator isn't discriminator. Option B (Circuit for filtering closely adjacent signals): Incorrect. Filter for adjacent signals isn't discriminator - discriminator detects FM signals. Filter isn't discriminator. Option C (Automatic band-switching circuit): Incorrect. Automatic band-switching isn't discriminator - discriminator detects FM signals. Band-switching isn't discriminator.
Exam Tip
Frequency discriminator = circuit for detecting FM signals. Think 'F'requency 'D'iscriminator = 'F'M 'D'etector. Frequency discriminators demodulate FM signals. Not FM generator, not filter, not band-switching - just FM detector.
Memory Aid
Frequency discriminator = circuit for detecting FM signals. Think 'F'requency 'D'iscriminator = 'F'M 'D'etector. Frequency discriminators demodulate FM signals. Important for demodulation.
Real-World Example
A frequency discriminator: It's a circuit for detecting FM signals. The discriminator converts frequency variations into amplitude variations (audio). This is what it is - FM detector.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E7E
Reference: 2024-2028 Question Pool · E7 - Practical Circuits
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E7E topic.