Confidence: Medium · Source: FCC ULS · As of 2026-09-14
N5MTB callsign genealogy
Currently held by MONHOLLON, JOHN MARK
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 N5MTB's current licensee, walking backwards.
- BILLIS, MATTHEW TTXgranted 2022-12-06cancelled 2022-12-24
Successor callsigns
Callsigns held now by people who previously held N5MTB.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N5MTB, oldest first.
- MONHOLLON, JOHN MARK OK1998-02-25 → cancelled 2010-02-26
- BILLIS, MATTHEW T TX2022-12-24 active