Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K9CFD callsign genealogy
Currently held by Yu, Thomas B
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 K9CFD's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held K9CFD.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K9CFD, oldest first.
- Yu, Thomas B IL2012-10-16 → cancelled 2024-12-04
- Brezina, Kenneth A IL2025-09-09 active