Basic Qualification · B-003 Station assembly, practice and safety · B-003-002-003
An FM transmitter's modulator:
- A as no effect on the frequency of the oscillator
- B alters the radio's output signal amplitude
- C produces amplitude changes in the oscillator
- D affects the frequency of the oscillator
Correct answer: D — affects the frequency of the oscillator. From the official ISED question bank, verified word for word.
Why
In frequency modulation, the modulator varies the pitch of the carrier wave by directly changing how fast the oscillator vibrates, which is why it affects the frequency of the oscillator. 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.