Basic Qualification · B-008 Interference and suppression · B-008-002-001
What devices would you install to reduce or eliminate interference to a home entertainment system from an HF transmitter?
- A Metal oxide varistors
- B Bypass inductors
- C Coils on ferrite cores
- D Bypass resistors
Correct answer: C — Coils on ferrite cores. From the official ISED question bank, verified word for word.
Why
Coils on ferrite cores act as a choke that blocks high-frequency radio energy from travelling along power or audio cables into your home entertainment system, while still letting normal electricity and sound pass through. 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.