Confidence: Medium · Source: FCC ULS · As of 2026-09-14
K4TBI callsign genealogy
Currently held by IRWIN, 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 K4TBI's current licensee, walking backwards.
- IRWIN, THOMAS BKYgranted 2003-09-03cancelled 2009-11-21
Successor callsigns
Callsigns held now by people who previously held K4TBI.
No current licensee on record previously held this callsign.