Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KR4YYZ callsign genealogy
Currently held by WITTHUN, JASON
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 KR4YYZ's current licensee, walking backwards.
- WITTHUN, JASONFLgranted 2023-08-01cancelled 2023-09-01
Successor callsigns
Callsigns held now by people who previously held KR4YYZ.
No current licensee on record previously held this callsign.