Basic Qualification · B-003 Station assembly, practice and safety · B-003-010-009
Un récepteur est muni de quatre filtres: un de 250 Hz, un de 500 Hz, un de 2,4 kHz et un de 6 kHz. Si vous écoutiez un signal en BLU, quel filtre utiliseriez-vous?
- A6 kHz
- B500 Hz
- C2,4 kHz
- D250 Hz
Correct answer: C — 2,4 kHz. Question tirée de la banque officielle d'ISDE.
Why
Single sideband voice needs about 2.4 kilohertz of bandwidth to sound clear, so the 2.4 kHz filter is the right choice because it passes the full range of human speech without cutting off important parts. The full explanation — and one for every question — is in Pro.
Practise this section
Station assembly, practice and safety is section B-003 of the Basic exam: Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.
Drill B-003 — free, no account