Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-006-006
Quel circuit audio, typiquement présent dans un émetteur FM, a pour effet d'atténuer les basses fréquences?
- AUn circuit de désaccentuation
- BUn circuit de préaccentuation
- CUn prédiviseur ("prescaler") audio
- DUn suppresseur hétérodyne
Correct answer: B — Un circuit de préaccentuation. Question tirée de la banque officielle d'ISDE.
Why
A pre-emphasis network boosts higher audio frequencies before transmission to make them stronger than lower ones, which helps overcome noise that naturally affects high pitches more. 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