Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KK9ZZ callsign genealogy
Currently held by UMBACH, STEVEN L
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 KK9ZZ's current licensee, walking backwards.
- N9ROUcancelledcancelled 1998-10-05
Successor callsigns
Callsigns held now by people who previously held KK9ZZ.
No current licensee on record previously held this callsign.