Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-002-007
Dans un amplificateur en grille commune utilisant une triode à vide, l'enroulement secondaire d'un transformateur est connecté directement au tube à vide. Ce transformateur fournit :
- AB- (polarisation)
- BB+ (haute tension)
- Cla tension d'écran
- Dla tension du filament
Correct answer: D — la tension du filament. Question tirée de la banque officielle d'ISDE.
Why
In a triode vacuum tube, the filament (or heater) must be warmed up to release electrons, and this heating requires a specific low-voltage supply. The full explanation — and one for every question — is in Pro.
Practise this section
Transmitters, modulation and processing is section A-005 of the Advanced exam: Transmitters, modulation and processing: AM, FM, SSB, keying, speech processing, and the numbers behind occupied bandwidth.
Drill A-005 — free, no account