Basic Qualification · B-003 Station assembly, practice and safety · B-003-002-002
The microphone of an FM transmitter:
- A has a different tone than other microphones
- B has a wider frequency range than other microphones
- C produces an electrical signal from air pressure changes
- D is quieter than AM or SSB microphones
Correct answer: C — produces an electrical signal from air pressure changes. From the official ISED question bank, verified word for word.
Why
A microphone works by turning the sound waves from your voice, which are tiny changes in air pressure, into an electrical signal that the radio can process. The full explanation — and one for every question — is in Pro.
Practise this section
Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.