Definition
An electronic circuit that converts variations in the frequency of an incoming signal into corresponding variations in voltage. It is most commonly used in the detector stage of an FM (frequency-modulated) receiver to recover the audio or data signal from the carrier wave.
Plain English
A circuit that listens to a radio signal whose frequency is wobbling up and down, and turns that wobble back into the original sound or information.
Context Anchor
Seen in avionics and radio receiver descriptions, especially when discussing how a receiver gets useful information out of a received signal.
Derivation
From the Latin discriminare, meaning 'to separate' or 'to distinguish between.' The circuit earns the name because it distinguishes between small differences in frequency and produces a different voltage for each one.
Why Pilots Care
Many aircraft navigation and communication systems rely on FM signals. The discriminator is what allows the receiver to pull useful information — voice, navigation data, or identification tones — out of the radio signal cleanly. When a discriminator is misaligned or failing, audio sounds distorted or navigation indications become unreliable.
Intuition Check
Do not read discriminator as a person making a judgment or showing unfair treatment. In electronics, it means a circuit that detects and separates small differences in frequency.
Example Sentence 1
The avionics technician traced the distorted audio to a misaligned discriminator in the FM receiver.
Example Sentence 2
A failing discriminator in the navigation radio produced distorted audio and unreliable bearing indications.