Basic Qualification · B-008 Interference and suppression · B-008-003-009
What term describes an unwanted oscillation in an amplifier or oscillator circuit?
- AHarmonic emission
- BParasitic oscillation
- CSecondary emission
- DFrequency instability
Correct answer: B — Parasitic oscillation. From the official ISED question bank, verified word for word.
Why
Parasitic oscillation describes an unwanted signal that a circuit generates on its own, often at a frequency it was not designed to handle, much like a parasite feeding off the main system. The full explanation — and one for every question — is in Pro.
Practise this section
Interference and suppression is section B-008 of the Basic exam: When things interfere: harmonics, overload, RFI to and from your station, filters, ferrites and how to fix the neighbour's TV.
Drill B-008 — free, no account