Offline Tool
CTCSS & DCS Decoder
CTCSS (PL) and DCS are the sub-audible codes that open an FM repeater. This lookup converts Hz to tone number and back so you can program encode/decode without mixing nearby tones.
Tone Hz to Motorola code reverse lookup and DCS reference. Works offline after your first visit.
CTCSS (PL) and DCS are the sub-audible codes that open an FM repeater. This lookup converts Hz to tone number and back so you can program encode/decode without mixing nearby tones.
Tone encode (TTone in CHIRP) is what you transmit so the repeater receiver opens. Tone squelch / TSQL is a receive filter so you only hear users sending the same tone. Many East TN machines need encode only; adding TSQL can hide a net if someone is slightly off-frequency.
Common local tones: 88.5 (NETNRC GMRS Johnson City), 136.5 (Kingsport GMRS), 203.5 (146.805 NETNRC 2 m), 77.0 (WR4CC 146.700), 100.0 (some UHF / MTEARS). DCS is a digital code used instead of CTCSS on a minority of machines — do not send both.
If you cannot access a repeater, the first checks are offset, then tone, then whether the machine is linked or down. Decoder tool plus offset plus a correction form if the published tone is wrong.
See also: Glossary: CTCSS / PL
Sub-audible tone that opens a repeater — must match programmed tone on your radio.
Yes. PL is Motorola’s trademark name. Hams say “PL 123.0” meaning CTCSS 123.0 Hz.
Only if the repeater owner recommends it or the output is noisy. Encode is the requirement; decode is optional comfort.
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