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Silent Key callsign harvesting
Web site news (2026-10-03)

K7AQ (since 1987)

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Maidenhead grid

FM19jd

53 active licensees across 13 ZIP codes centered in this square. Each dot is a ZIP code, sized by licensee count.

ZIP codes

ZIP	City	Hams
20877	Gaithersburg, MD	39
20880	Washington Grove, MD	4
20859	Potomac, MD	3
20884	Gaithersburg, MD	3
20827	Bethesda, MD	1
20848	Rockville, MD	1
20875	Germantown, MD	1
20898	Gaithersburg, MD	1
20813	Bethesda, MD	0
20889	Bethesda, MD	0
20894	Bethesda, MD	0
20897	Suburb Maryland Fac, MD	0
20899	Gaithersburg, MD	0