Confidence: Medium · Source: FCC ULS · As of 2026-09-09

W4MBU

Active

MARTINEZ JR, MAURICIO C

Location: MIAMI, FL
Class: General
Granted: 2017-02-14
Expires: 2027-02-14
Previous call: KB4MBU
FRN: 0013724604

Get notified about status changes and vanity availability for this callsign.

Vanity availability

Held

Currently held

W4MBU is held by an active license; it isn't a vanity slot right now.

Vanity availability dates are computed from FCC §97.19's hold periods: 2 years from the cancellation date for cancelled or terminated licenses, 4 years from the expiration date for expired licenses (2-year renewal grace + 2-year hold).

Callsign genealogy

Full chain →

Previously held by current licensee

KB4MBUactive· T
Alfaro, Daphne EFLgranted 2022-02-08
KO4RPBcancelled· T
Alfaro, Daphne EFLgranted 2021-06-29cancelled 2022-02-08

License history

0 events

No recorded events.

More vanity slots coming available

From Florida

All →

K4HCL 2026-09-09
KG4UZU 2026-09-09
KG4UZX 2026-09-09
KK4LMR 2026-09-09
W3EFZ 2026-09-09

Starting with W4

All →

W4HKO FL · 2026-09-09
W4IDI AL · 2026-09-10
W4YAU TN · 2026-09-10
W4CVH VA · 2026-09-12
W4QDZ NC · 2026-09-13

Full history → Vanity availability → Callsign genealogy →