BasicB-002-001-005
What is a CTCSS tone?
B
Answer
Licensing, station identification, and operation
Type
A
A signal used for telemetry by amateur radio satellites
B
A sub-audible tone that activates a receiver audio output when present
C
A tone used by repeaters to mark the end of a transmission
D
A signal used for radio control of model craft
Answer Notes
CTCSS (Continuous Tone-Coded Squelch System) is a low-frequency, sub-audible tone transmitted alongside your voice signal. Its primary purpose is to activate the audio output of a specific receiver or repeater, allowing it to open its squelch and pass the signal through to the speaker.
This system is widely used to prevent repeaters from being keyed up by random noise, electrical interference, or distant stations operating on the same frequency. Users simply program their radio to transmit the correct matching tone required by the local repeater.
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