Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KD5JEF callsign genealogy
Currently held by Niewodniczanski, Tomasz
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 KD5JEF's current licensee, walking backwards.
- Verdin, Jeffery RMSgranted 2021-05-26cancelled 2021-06-15
Successor callsigns
Callsigns held now by people who previously held KD5JEF.
- Niewodniczanski, TomaszTXgranted 2020-03-02
All historical holders
Every license row we've seen with the callsign KD5JEF, oldest first.
- Niewodniczanski, Tomasz TX2000-02-05 → cancelled 2000-03-07
- Verdin, Jeffery R MS2021-06-15 active