Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AA4MX callsign genealogy
Currently held by Mc Donald, John 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 AA4MX's current licensee, walking backwards.
- Mc Donald, John OFLgranted 2007-10-26cancelled 2015-03-21
Successor callsigns
Callsigns held now by people who previously held AA4MX.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign AA4MX, oldest first.
- MC DONALD, RALPH L DE1998-01-12 → cancelled 2007-05-18
- Mc Donald, John O FL2025-02-04 active