Advanced Qualification · A-005 Transmitters, modulation and processing · A-005-005-001
Si un signal FM a une excursion maximale de fréquence de 3 000 Hz de part et d'autre de la fréquence porteuse lorsque la fréquence modulante est de 1 000 Hz, quel est l'indice de modulation?
- A1 000
- B3
- C0,3
- D3 000
Correct answer: B — 3. Question tirée de la banque officielle d'ISDE.
Why
The modulation index is simply the ratio of how far the frequency swings to how fast it swings. 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