Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KN1J callsign genealogy
Currently held by CZAJKA, CHARLES J
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 KN1J's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held KN1J.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KN1J, oldest first.
- CZAJKA, CHARLES J CT1994-07-15 → cancelled 2006-07-18
- Nakase, Koichi MA2026-05-19 active