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Confidence: Medium · Source: FCC ULS · As of 2026-09-14

KZ4OY callsign genealogy

Currently held by KOPECKY, MATTHEW

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 KZ4OY's current licensee, walking backwards.

  1. KM4ATcancelled· E
    KOPECKY, MATTHEWKYgranted 2024-07-30cancelled 2024-12-24
  2. KZ4BUcancelled· E
    KOPECKY, MATTHEWKYgranted 2023-10-20cancelled 2024-07-30
  3. KQ4LXWcancelled· E
    KOPECKY, MATTHEWKYgranted 2023-10-20cancelled 2023-11-06

Successor callsigns

Callsigns held now by people who previously held KZ4OY.

  1. KO4Mactive· E
    KOPECKY, MATTHEWKYgranted 2026-02-27
← Back to KZ4OY License history →