Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AB4FW callsign genealogy
Currently held by FRIEDERICH, RUDOLF J
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 AB4FW's current licensee, walking backwards.
The current licensee has not held any other callsign on record.
Successor callsigns
Callsigns held now by people who previously held AB4FW.
- FRIEDERICH, RUDOLF JTNgranted 2013-11-09cancelled 2024-02-11