Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K5SIO callsign genealogy
Currently held by SCHILLING III, RALPH 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 K5SIO's current licensee, walking backwards.
- SCHILLING III, RALPH FCAgranted 2007-08-10cancelled 2015-09-29
Successor callsigns
Callsigns held now by people who previously held K5SIO.
No current licensee on record previously held this callsign.