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

W9ZU callsign genealogy

Currently held by Castaldo, John N

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 W9ZU's current licensee, walking backwards.

  1. AG4YCcancelled· E
    Castaldo, John NSCgranted 2003-02-12cancelled 2011-08-30
  2. KG6FLEcancelled· E
    Castaldo, John NSCgranted 1994-12-29cancelled 2003-02-12
  3. KE6PNUcancelled· G
    Castaldo, John NCAgranted 1994-12-29cancelled 2001-03-07
  4. N9EQB
    no FCC ULS record on file

Successor callsigns

Callsigns held now by people who previously held W9ZU.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign W9ZU, oldest first.

  • KELLEY, JAY L IN
    2000-06-20 → cancelled 2009-08-02
  • Castaldo, John N SC
    2021-07-01 active
← Back to W9ZU License history →