Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4BJO callsign genealogy
Currently held by Osterheim, Brian
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 K4BJO's current licensee, walking backwards.
- Osterheim, BrianSCgranted 2021-03-03cancelled 2022-04-29
Successor callsigns
Callsigns held now by people who previously held K4BJO.
No current licensee on record previously held this callsign.