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

KW4ZO callsign genealogy

Currently held by Hacker, Leonard D

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 KW4ZO's current licensee, walking backwards.

  1. K4MOPcancelled· E
    Hacker, Leonard DFLgranted 2016-02-13cancelled 2016-11-21
  2. KK4WHBcancelled· G
    Hacker, Leonard DFLgranted 2014-01-09cancelled 2016-02-13

Successor callsigns

Callsigns held now by people who previously held KW4ZO.

  1. K4ATGactive· E
    Hacker, Leonard DGAgranted 2017-02-28
← Back to KW4ZO License history →