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Confidence: Medium · Source: FCC ULS · As of 2026-09-12

KX3O callsign genealogy

Currently held by COOPER, CHARLES E

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 KX3O's current licensee, walking backwards.

  1. KI7OSEcancelled· E
    Welch, JasonWAgranted 2017-07-05cancelled 2017-09-19

Successor callsigns

Callsigns held now by people who previously held KX3O.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KX3O, oldest first.

  • COOPER, CHARLES E PA
    2005-06-06 → cancelled 2017-08-31
  • Welch, Jason WA
    2017-09-19 active