S-31
| Brand | Hallicrafters |
| Manufacturer | The Hallicrafters Co. |
| Function | Radio Tuner |
| Produced | 1941-1942 |
| Country | United States |
| Form Factor | 19" Rackmount |
| Signal Path | Analog Hardware |
| Dimensions | 48.3 × 22.2 × 0 cm (W × H × D) |
| Power | 115-125VAC, 60Hz 120W |
| Tuning Range (AM) | 540kHz-1650kHz |
| Tuning Range (FM) | 40MHz-51MHz |
| Output Power | 130mW |
| Output Impedance | 500-5000Ω |
| MSRP (1941) | $69.50 |
| Channels | 1 Channel |
| Notes | Intended for use with S-31A amplifier. Also came in RSC-2 Broadcast Receiving Station for PA installation. |