Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AI4DF callsign genealogy
Currently held by Matsumoto, Kiyoshi
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 AI4DF'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 AI4DF.
- Matsumoto, KiyoshiTNgranted 2014-05-03cancelled 2026-06-26