Basic Qualification · B-003 Station assembly, practice and safety · B-003-013-003
What term defines the change in frequency caused by modulation in an FM transmitter?
- A Shift
- B Modulation index
- C Deviation
- D Spectrum spread
Correct answer: C — Deviation. From the official ISED question bank, verified word for word.
Why
In frequency modulation, the carrier wave's frequency moves up and down from its centre point based on the audio signal; this specific amount of movement is called deviation. 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.