Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KC9OZK callsign genealogy
Currently held by Feldhake, Mark A
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 KC9OZK'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 KC9OZK.
- Feldhake, Mark AILgranted 2019-01-30