Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-002-008
Dans un amplificateur en grille commune utilisant une triode à vide, quelle est la tension B+ nécessaire pour produire une sortie de 400 watts à 400 mA lorsque le rendement est d'environ 50 %?
- A3 000 volts
- B1 000 volts
- C2 000 volts
- D500 volts
Correct answer: C — 2 000 volts. Question tirée de la banque officielle d'ISDE.
Why
To get 400 watts out with 50 percent efficiency, the amplifier must draw 800 watts of power from the power 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