Confidence: Medium · Source: FCC ULS · As of 2026-09-12
N0BTO callsign genealogy
Currently held by MUELLER, CRAIG L
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 N0BTO's current licensee, walking backwards.
- Oswald, Brian TIAgranted 2004-02-18cancelled 2004-04-13
Successor callsigns
Callsigns held now by people who previously held N0BTO.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N0BTO, oldest first.
- MUELLER, CRAIG L TN1987-10-06 → cancelled 1999-10-07
- Oswald, Brian T IA2025-08-16 active