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

W4ZMM callsign genealogy

Currently held by MORRISON, WILLIAM T

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 W4ZMM's current licensee, walking backwards.

  1. KN4Bactive· E
    TURBEVILLE JR, ROBERT LSCgranted 2023-01-13
  2. K4RLTactive· E
    Trevillian Jr, Richard LFLgranted 2024-12-31
  3. KJ4TUJcancelled· E
    Trevillian Jr, Richard LTNgranted 2010-04-05cancelled 2015-01-10

Successor callsigns

Callsigns held now by people who previously held W4ZMM.

  1. W4SSTactive· E
    MORRISON, WILLIAM TNCgranted 2020-05-12
  2. KN4Bcancelled· E
    MORRISON, WILLIAM TNCgranted 1998-12-01cancelled 2001-02-09

All historical holders

Every license row we've seen with the callsign W4ZMM, oldest first.

  • MORRISON, WILLIAM T NC
    2010-12-23 → cancelled 2020-05-12
  • MORRISON, WILLIAM T
    — → cancelled 1998-12-01
← Back to W4ZMM License history →