Confidence: Medium · Source: FCC ULS · As of 2026-09-12
NJ4G callsign genealogy
Currently held by KOPPEN, CHARLES E
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 NJ4G's current licensee, walking backwards.
- FREDERICK, JAMES BFLgranted 2013-06-05cancelled 2016-10-04
Successor callsigns
Callsigns held now by people who previously held NJ4G.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign NJ4G, oldest first.
- KOPPEN, CHARLES E FL2005-03-24 → cancelled 2014-09-14
- FREDERICK, JAMES B FL2016-10-04 active