Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KC4OS callsign genealogy
Currently held by RYSNER, ROBERT 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 KC4OS's current licensee, walking backwards.
- RYSNER, ROBERT FFLgranted 2008-10-03cancelled 2016-02-12
Successor callsigns
Callsigns held now by people who previously held KC4OS.
No current licensee on record previously held this callsign.