Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K0CFS callsign genealogy
Currently held by CROOK, SHELDON F
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 K0CFS's current licensee, walking backwards.
- Young, BrianKSgranted 2024-06-26cancelled 2025-08-22
Successor callsigns
Callsigns held now by people who previously held K0CFS.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K0CFS, oldest first.
- CROOK, SHELDON F KS1997-06-17 → cancelled 1999-12-21
- CROOK, SHELDON F AZ2013-06-04 → cancelled 2025-07-23
- Young, Brian C KS2025-08-22 active