Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4ZAX callsign genealogy
Currently held by MC CLURE, JACK C
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 K4ZAX's current licensee, walking backwards.
- King, JosephFLgranted 2021-03-11cancelled 2021-03-30
Successor callsigns
Callsigns held now by people who previously held K4ZAX.
- Shefte, John dNCgranted 2017-04-11
All historical holders
Every license row we've seen with the callsign K4ZAX, oldest first.
- MC CLURE, JACK C FL1990-06-05 → cancelled 2002-06-06
- Shefte, John D NC2016-04-08 → cancelled 2017-04-11
- King, Joseph J FL2021-03-30 active