Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KK7OSO callsign genealogy
Currently held by Marbach, Donald E
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 KK7OSO's current licensee, walking backwards.
- Marbach, Donald EAZgranted 2020-09-17cancelled 2020-10-06
Successor callsigns
Callsigns held now by people who previously held KK7OSO.
- Marbach, Donald EAZgranted 2022-05-24