Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KZ4TO callsign genealogy
Currently held by Spacil, Petr
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 KZ4TO's current licensee, walking backwards.
- Spacil, PetrVAgranted 2025-05-06cancelled 2025-06-03
Successor callsigns
Callsigns held now by people who previously held KZ4TO.
No current licensee on record previously held this callsign.