Confidence: Medium · Source: FCC ULS · As of 2026-09-09
KB4KB callsign genealogy
Currently held by Bielefeldt, Karl K
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 KB4KB's current licensee, walking backwards.
- Bielefeldt, Karl KALgranted 2000-09-28cancelled 2010-04-27
Successor callsigns
Callsigns held now by people who previously held KB4KB.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KB4KB, oldest first.
- TBONE PACKET ASSOCIATION TN1997-09-17 → cancelled 2009-09-18
- Bielefeldt, Karl K AL2020-04-25 active