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

WO9U callsign genealogy

Currently held by CZERWONKA, TIMOTHY J

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 WO9U's current licensee, walking backwards.

  1. N9ILScancelled· E
    Martinez, Enrique AFLgranted 2017-08-02cancelled 2020-08-18
  2. KF9MDcancelled· E
    Martinez, Enrique AINgranted 2006-10-19cancelled 2007-10-30
  3. AD7FEcancelled· E
    Martinez, Enrique AAZgranted 2004-06-19cancelled 2006-10-19
  4. AB9JSactive· E
    STEVENS, JOHN WAZgranted 2016-07-26
  5. N9JYOcancelled· E
    STEVENS, JOHN WAZgranted 2014-02-28cancelled 2016-07-26

Successor callsigns

Callsigns held now by people who previously held WO9U.

No current licensee on record previously held this callsign.

← Back to WO9U License history →