Advanced Qualification · A-006 Receivers · A-006-002-009
Quel étage d'un récepteur combine un signal d'entrée de 14,250 MHz avec un signal de 13,795 MHz de l'oscillateur local pour produire un signal de fréquence intermédiaire de 455 kHz?
- AL'oscillateur de battement ("BFO")
- BL'oscillateur à fréquence variable (VFO)
- CLe multiplicateur
- DLe mélangeur
Correct answer: D — Le mélangeur. Question tirée de la banque officielle d'ISDE.
Why
A mixer is the stage that takes two different radio frequencies and combines them to create a new frequency, which in this case is the difference between 14.25 MHz and 13.795 MHz, resulting in the 455-kilohertz intermediate frequency. 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