Confidence: Medium · Source: FCC ULS · As of 2026-09-12
W4MDB callsign genealogy
Currently held by Bonsall, Michael D
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 W4MDB's current licensee, walking backwards.
- Bonsall, Michael DFLgranted 2011-03-18cancelled 2011-05-17
Successor callsigns
Callsigns held now by people who previously held W4MDB.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W4MDB, oldest first.
- BIG LAGOON FRIENDSHIP RADIO CLUB FL1997-09-17 → cancelled 2009-09-18
- Bonsall, Michael D FL2021-03-17 active