| Abbreviation | Definition |
|---|---|
| SOM | Start Of Message |
| SOS | International Distress Signal |
| SOS | Send Out Signal |
| SOSB | Single Operator, Single band |
| SPA | Slot Plane Antenna |
| SPKR | Speaker |
| SPLAT | Signal Propagation Loss And Terrain |
| SQ | Sound Quality |
| SQL | SQueLch |
| SR | Short Repeat |
| SR | Standard Radio |
| SRARC | Snake River Amateur Radio Club |
| SRD | Short Range Devices |
| SS | Signal Strength |
| SSB | Single SideBand |
| SSB | Single-sideband modulation |
| SSBSC | Single-Sideband Suppressed Carrier |
| SSN | Sun Spot Number |
| SST | Solid State Transmitter |
| STANDBYONE | I need you to wait for a minute/second |