Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4HMJ callsign genealogy
Currently held by SPARKS, ROBERT O
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 K4HMJ's current licensee, walking backwards.
- MacGregor, Scott PGAgranted 2018-09-12cancelled 2018-10-02
Successor callsigns
Callsigns held now by people who previously held K4HMJ.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K4HMJ, oldest first.
- SPARKS, ROBERT O AL1995-08-22 → cancelled 2007-08-23
- MacGregor, Scott P GA2018-10-02 active