Confidence: Medium · Source: FCC ULS · As of 2026-09-12
AC1DU callsign genealogy
Currently held by Shamshak Sr, Thomas P
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 AC1DU's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held AC1DU.
No current licensee on record previously held this callsign.