Confidence: Medium · Source: FCC ULS · As of 2026-09-14
K9GRO callsign genealogy
Currently held by BROOK, ALAN 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 K9GRO's current licensee, walking backwards.
- Brook, Stewart CMSgranted 2025-11-26cancelled 2026-01-21
Successor callsigns
Callsigns held now by people who previously held K9GRO.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K9GRO, oldest first.
- BROOK, ALAN J IL2015-04-08 → cancelled 2024-01-28
- Brook, Stewart C MS2026-01-21 active