Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4JFR callsign genealogy
Currently held by Robertson IV, James F
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 K4JFR's current licensee, walking backwards.
- Robertson IV, James FCAgranted 2009-10-30cancelled 2010-04-23
Successor callsigns
Callsigns held now by people who previously held K4JFR.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K4JFR, oldest first.
- THARP, BRYCE W NC1998-02-25 → cancelled 2010-02-26
- Robertson IV, James F CA2020-03-17 active