Basic Qualification · B-008 Interference and suppression · B-008-005-007
Un fort signal brouilleur est très proche de votre fréquence de réception. Quel type de filtre peut le supprimer efficacement?
- AUn filtre réjecteur ("notch")
- BUn filtre passe-haut
- CUn filtre passe-bas
- DUn filtre coupe-bande
Correct answer: A — Un filtre réjecteur ("notch"). Question tirée de la banque officielle d'ISDE.
Why
A Notch filter is the right choice because it acts like a very narrow trap, removing just one specific frequency while letting everything else pass. The full explanation — and one for every question — is in Pro.
Practise this section
Interference and suppression is section B-008 of the Basic exam: When things interfere: harmonics, overload, RFI to and from your station, filters, ferrites and how to fix the neighbour's TV.
Drill B-008 — free, no account