MDC stands for Motorola Data Communications. It is an audio-frequency shift keying protocol used primarily over analog FM radio channels. Radios use it to send digital bursts for features like unit identification, emergency alarms, and remote radio disabling. The distinctive squawk sound heard at the beginning or end of a transmission is the MDC data burst.
Heard on the job
Make sure the fleet is programmed with MDC 1200 so dispatch can see who's keying up.
Also heard as
- MDC-1200
Related terms
Squelch
A circuit function that mutes the audio output of a receiver when no strong signal is present.
In-band signaling
The transmission of network control signals over the same channel used for the actual voice or data payload.
Hot microphone
A microphone that is actively transmitting or recording without the user actively pressing a button.