| Business | Phone |
| Motorola Communications 1803 Sulphur Spring Rd, Baltimore 21227 | (410) 712-6200 |
| Communications Marketing Assoc 6606 Baythorne Rd, Baltimore 21209 | (410) 653-5100 |
| Horizon Electronics Inc 5934 Belle Grove Rd, Baltimore 21225 | (410) 789-4343 |
| Lac-Fl Two-Way 1746 Abbotston St, Baltimore 21218 | (410) 366-5234 |
| Teltronics Inc 4220 Shannon Dr # L, Baltimore 21213 | (410) 488-0100 |