Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KI4APJ callsign genealogy
Currently held by Markun, Leonard
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 KI4APJ's current licensee, walking backwards.
- KQ4ZEIcancelledIsothermal Amateur Radio ClubNCgranted 2024-11-28cancelled 2024-12-17
Successor callsigns
Callsigns held now by people who previously held KI4APJ.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KI4APJ, oldest first.
- Markun, Leonard GA2003-05-30 → cancelled 2015-06-02
- Isothermal Amateur Radio Club NC2024-12-17 active