Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KB4MBU callsign genealogy
Currently held by MARTINEZ JR, MAURICIO C
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 KB4MBU's current licensee, walking backwards.
- Alfaro, Daphne EFLgranted 2021-06-29cancelled 2022-02-08
Successor callsigns
Callsigns held now by people who previously held KB4MBU.
- MARTINEZ JR, MAURICIO CFLgranted 2017-02-14
All historical holders
Every license row we've seen with the callsign KB4MBU, oldest first.
- MARTINEZ JR, MAURICIO C FL2015-12-15 → cancelled 2017-02-14
- Alfaro, Daphne E FL2022-02-08 active