Confidence: Medium · Source: FCC ULS · As of 2026-09-12
N1TDF callsign genealogy
Currently held by SULLIVAN, WILLIAM G
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 N1TDF's current licensee, walking backwards.
- SULLIVAN ANDREWS, HILARY AMAgranted 2003-10-22cancelled 2004-09-15
Successor callsigns
Callsigns held now by people who previously held N1TDF.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N1TDF, oldest first.
- SULLIVAN, WILLIAM G MA1996-07-10 → cancelled 2002-07-05
- SULLIVAN ANDREWS, HILARY A MA2014-09-12 active