Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AB1TR callsign genealogy
Currently held by TOLENTINO, ROBERT M
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 AB1TR's current licensee, walking backwards.
- TOLENTINO, ROBERT MVAgranted 2015-06-19cancelled 2017-04-28
Successor callsigns
Callsigns held now by people who previously held AB1TR.
- Grosvenor III, Thomas HFLgranted 2013-08-27cancelled 2025-08-28
All historical holders
Every license row we've seen with the callsign AB1TR, oldest first.
- Grosvenor III, Thomas H MA2013-07-19 → cancelled 2013-08-27
- TOLENTINO, ROBERT M MA2017-04-28 active