Advanced Qualification · A-006 Receivers · A-006-004-010
Which two variables primarily determine the behaviour of an automatic gain control (AGC) loop?
- A Blanking level and slope
- B Slope and bandwidth
- C Clipping level and hang time
- D Threshold and decay time
Correct answer: D — Threshold and decay time. From the official ISED question bank, verified word for word.
Why
An automatic gain control loop relies on two main settings: the threshold, which is the signal level that triggers the gain reduction, and the decay time, which is how long the system waits before returning the gain to normal after the strong signal fades. The full explanation — and one for every question — is in Pro.
Practise this section
Receivers: superheterodyne design, selectivity, sensitivity, images, AGC and noise.