uls-tracker
Sign in
Confidence: Medium · Source: FCC ULS · As of 2026-09-14

K0XX callsign genealogy

Currently held by FRAZIER, JOHN M

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 K0XX's current licensee, walking backwards.

  1. AK6LMcancelled· E
    xie, XunCAgranted 2024-12-28cancelled 2025-03-08
  2. KO6HIHcancelled· E
    xie, XunCAgranted 2024-12-28cancelled 2025-02-10

Successor callsigns

Callsigns held now by people who previously held K0XX.

  1. W4BRactive· E
    FRAZIER, JOHN MFLgranted 2023-02-17

All historical holders

Every license row we've seen with the callsign K0XX, oldest first.

  • KOWALSKI, THOMAS M KS
    2007-01-27 → cancelled 2016-02-03
  • FRAZIER, JOHN M FL
    2018-02-23 → cancelled 2023-02-17
  • Xie, Xun CA
    2025-03-08 active
← Back to K0XX License history →