Basic Qualification · B-008 Interference and suppression · B-008-004-003
Why are harmonic emissions from an amateur radio station not wanted?
- A They may result in excessive power dissipation
- B They may overload a nearby transmitter
- C They may interfere with stations on adjacent frequencies
- D They may cause interference to other stations
Correct answer: D — They may cause interference to other stations. From the official ISED question bank, verified word for word.
Why
Harmonic emissions are extra signals your transmitter creates at multiples of your chosen frequency, and they are unwanted because they may cause interference to other stations operating on those different frequencies. The full explanation — and one for every question — is in Pro.
Practise this section
When things interfere: harmonics, overload, RFI to and from your station, filters, ferrites and how to fix the neighbour's TV.