Basic Qualification · B-008 Interference and suppression · B-008-004-009
Which of the following may cause excessive harmonics in a transmitter?
- A Internal antenna tuner malfunction
- B Overdriven stages
- C Use of a non-resonant antenna
- D Defective driver circuit
Correct answer: B — Overdriven stages. From the official ISED question bank, verified word for word.
Why
Overdriven stages happen when you push a transmitter's amplifier too hard, forcing it to clip the signal and create extra frequencies called harmonics that interfere with other bands. 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.