Basic Qualification · B-003 Station assembly, practice and safety · B-003-002-003
Le modulateur d'un émetteur FM:
- Afait varier la fréquence de l'oscillateur
- Bn'a aucun effet sur la fréquence de l'oscillateur
- Cmodifie l'amplitude du signal de sortie de l'émetteur
- Dproduit des changements d'amplitude dans l'oscillateur
Correct answer: A — fait varier la fréquence de l'oscillateur. Question tirée de la banque officielle d'ISDE.
Why
In frequency modulation, the modulator varies the pitch of the carrier wave by directly changing how fast the oscillator vibrates, which is why it affects the frequency of the oscillator. The full explanation — and one for every question — is in Pro.
Practise this section
Station assembly, practice and safety is section B-003 of the Basic exam: Building a station safely: power supplies, grounding, RF exposure, lightning, feedline routing, and what a transmitter, receiver and transceiver actually do.
Drill B-003 — free, no account