Amateur Radio Callsigns in ZIP Code: 21757
| Callsign | Name | City | State | Country |
|---|---|---|---|---|
| KB3ASV | GARVER, CHRISTINE M | DETOUR | MD | United States |
| KB3ATV | GARVER, JASON D | KEYMAR | MD | United States |
| N3PMC | PARMERLEE, DAVID A | Keymar | MD | United States |
| N3QKU | GREENE, HAROLD I | KEYMAR | MD | United States |
| W3CA | LUKE, ROBERT G | Keymar | MD | United States |
| KC3QPJ | Wunder, Aaron J | Keymar | MD | United States |
| KC3QPL | Thomas, Jared M | Keymar | MD | United States |