| Abbreviation | Definition |
|---|---|
| CPM | Continuous Phase Modulation |
| CPS | Carrier Pre-Select |
| CQ | A recognized amateur radio call signal to the world |
| CQ | General Call |
| CQCQ | CQ is the international ham radio call meaning "anyone listening?" It's often repeated two or three times, trying to start a conversation with someone on a channel (frequency). |
| CQD | Come Quick Danger |
| CRAQ | Club Radio Amateur de Qu??bec |
| CRAQ | Club Radio Amateur de Québec |
| CRES | Columbus Radio Enthusiasts Society |
| CREST | Citizens Radio Emergency Service Team |
| CSQ | Carrier Squelch |
| CSS | Carrier Sense System |
| CSS | Curvature Scale Space |
| CTRC | Carnegie Tech Radio Club |
| CW | Continuous Wave |
| CW | Continuous Waveform |
| DAH | INTERNATIONAL Morse Code 'DASH' PRONOUNCED AS SHORT 'A', AS IN 'LA' |
| DAR | Digital Analog Radio |
| DARA | Dayton Amateur Radio Association |
| DARC | Dallas Amateur Radio Club |