Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AD0IO callsign genealogy
Currently held by DONALDSON, RONALD 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 AD0IO's current licensee, walking backwards.
- DONALDSON, RONALD JCOgranted 2014-03-26cancelled 2014-05-02
Successor callsigns
Callsigns held now by people who previously held AD0IO.
No current licensee on record previously held this callsign.