Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KY4KO callsign genealogy
Currently held by Stambaugh, Harold M
The FCC publishes a previous_call_sign on
every amateur license — a self-link to the licensee's prior callsign.
Following those links produces the chain below.
Previous callsigns
Older callsigns held by KY4KO's current licensee, walking backwards.
- Stambaugh, Harold MKYgranted 2014-12-23cancelled 2015-03-17
Successor callsigns
Callsigns held now by people who previously held KY4KO.
- Mahaney, Thomas SGAgranted 2008-02-22cancelled 2008-05-30
All historical holders
Every license row we've seen with the callsign KY4KO, oldest first.
- Mahaney, Thomas S GA2007-06-05 → cancelled 2008-02-22
- Stambaugh, Harold M KY2024-12-28 active