Confidence: Medium · Source: FCC ULS · As of 2026-09-14
NT3O callsign genealogy
Currently held by SIBLEY, DAVID A
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 NT3O's current licensee, walking backwards.
- Lazarz, Charles FPAgranted 2002-02-05cancelled 2008-04-15
Successor callsigns
Callsigns held now by people who previously held NT3O.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign NT3O, oldest first.
- SIBLEY, DAVID A PA1989-01-31 → cancelled 2001-02-01
- LAZARZ, CHARLES F PA2018-01-18 active