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

KB4OZ callsign genealogy

Currently held by Rivera, Osvaldo

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 KB4OZ's current licensee, walking backwards.

  1. AJ4EPcancelled· E
    Rivera, OsvaldoFLgranted 2002-07-16cancelled 2008-02-15
  2. KP4LEUcancelled· E
    Rivera, OsvaldoFLgranted 2002-07-16cancelled 2008-01-23
  3. WP3KScancelled· G
    Rivera-Soto, OsvaldoPRgranted 2001-05-02cancelled 2002-07-16

Successor callsigns

Callsigns held now by people who previously held KB4OZ.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KB4OZ, oldest first.

  • COOPER, ROBERT D KY
    1994-05-24 → cancelled 2006-05-25
  • Rivera, Osvaldo FL
    2008-02-15 → cancelled 2020-02-19
← Back to KB4OZ License history →