Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KZ4DY callsign genealogy
Currently held by Guilfoyle, Joseph C
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 KZ4DY's current licensee, walking backwards.
- Guilfoyle, Joseph CVAgranted 2023-08-24cancelled 2024-02-06
Successor callsigns
Callsigns held now by people who previously held KZ4DY.
No current licensee on record previously held this callsign.