Confidence: Medium · Source: FCC ULS · As of 2026-09-12
WZ1O callsign genealogy
Currently held by VON DER HEYDT, WILLIAM 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 WZ1O's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held WZ1O.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign WZ1O, oldest first.
- VON DER HEYDT, WILLIAM A MA2011-11-03 → cancelled 2023-12-12
- Hatch, Vance A CA2024-01-09 active