Advanced Qualification · A-006 Receivers · A-006-004-001
Quel circuit faut-il ajouter à un récepteur FM pour restaurer proportionnellement les basses fréquences atténuées?
- AUn suppresseur hétérodyne
- BUn circuit de désaccentuation
- CUn circuit de préaccentuation
- DUn prédiviseur ("prescaler") audio
Correct answer: B — Un circuit de désaccentuation. Question tirée de la banque officielle d'ISDE.
Why
An FM receiver uses a de-emphasis network to boost the lower audio frequencies that were intentionally weakened during transmission to reduce background noise. The full explanation — and one for every question — is in Pro.
Practise this section
Receivers is section A-006 of the Advanced exam: Receivers: superheterodyne design, selectivity, sensitivity, images, AGC and noise.
Drill A-006 — free, no account