Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KB9OIS callsign genealogy
Currently held by Koehler III, Charles J
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 KB9OIS's current licensee, walking backwards.
The current licensee has not held any other callsign on record.
Successor callsigns
Callsigns held now by people who previously held KB9OIS.
- Koehler III, Charles JWIgranted 2017-03-28