Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KF4OS callsign genealogy
Currently held by Henderson, John T
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 KF4OS's current licensee, walking backwards.
- WB3EYTno FCC ULS record on file
Successor callsigns
Callsigns held now by people who previously held KF4OS.
No current licensee on record previously held this callsign.