Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KO4ASF callsign genealogy
Currently held by RUDOLPH, JOHN S
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 KO4ASF'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 KO4ASF.
- RUDOLPH, JOHN SKYgranted 2020-01-14cancelled 2020-02-01