Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K5OSU callsign genealogy
Currently held by STALCUP, RANDALL 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 K5OSU's current licensee, walking backwards.
- BREWER, JOHN STXgranted 2022-12-16cancelled 2025-06-07
Successor callsigns
Callsigns held now by people who previously held K5OSU.
- STALCUP, RANDALL JARgranted 2022-05-17
All historical holders
Every license row we've seen with the callsign K5OSU, oldest first.
- STALCUP, RANDALL J OK2020-04-04 → cancelled 2022-05-17
- BREWER, JOHN TX2025-06-07 active