Advanced Qualification · A-006 Receivers · A-006-001-009
L'oscillateur local d'un récepteur à simple conversion de fréquence dont la fréquence intermédiaire est de 9 MHz fonctionne à 16 MHz. La fréquence de syntonisation est de :
- A9 MHz
- B7 MHz
- C16 MHz
- D21 MHz
Correct answer: B — 7 MHz. Question tirée de la banque officielle d'ISDE.
Why
The receiver tunes to 7 MHz because the local oscillator mixes with the incoming signal to create the intermediate frequency, meaning the difference between the 16 MHz oscillator and the 9 MHz intermediate frequency equals the tuned signal. 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