Amateur Radio Callsigns in ZIP Code: 21639
| Callsign | Name | City | State | Country |
|---|---|---|---|---|
| KB0JJN | HARSHMAN, WILLIAM P | GREENSBORO | MD | United States |
| N3ZSV | BENNETT, ROBERT W | Greensboro | MD | United States |
| N4ISI | WEEDMAN, MICHAEL A | GREENSBORO | MD | United States |
| ND3G | PURSLEY, RICHARD L | Not Hispanic or Lati | MD | United States |
| WI3H | SPIERING, MARK D | GREENSBORO | MD | United States |
| W3FA | BRUCE, JAMES D | GREENSBORO | MD | United States |
| KB3QLY | Stoner III, Edward J | Greensboro | MD | United States |
| NI3Q | Firefighters Amateur Radio Society | Greensboro | MD | United States |