Confidence: Medium · Source: FCC ULS · As of 2026-09-12
WT4O callsign genealogy
Currently held by SWICK SR, CHARLES E
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 WT4O's current licensee, walking backwards.
- KI4DOWcancelledNORTH AMERICA CONTEST CLUBFLgranted 2004-01-07cancelled 2012-08-28
Successor callsigns
Callsigns held now by people who previously held WT4O.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign WT4O, oldest first.
- SWICK SR, CHARLES E FL2000-05-17 → cancelled 2012-08-08
- NORTH AMERICA CONTEST CLUB FL2022-07-02 active