Basic Qualification · B-003 Station assembly, practice and safety · B-003-003-004
In a superheterodyne receiver, which stage sets the received frequency?
- A RF amplifier
- B IF filter
- C Beat frequency oscillator
- D Local oscillator
Correct answer: D — Local oscillator. From the official ISED question bank, verified word for word.
Why
The local oscillator generates a signal that mixes with the incoming radio wave to create a fixed intermediate frequency, effectively deciding which station you hear by tuning to a specific frequency. 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.