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

K5MMO callsign genealogy

Currently held by DU BOIS, RALPH M

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 K5MMO's current licensee, walking backwards.

  1. W0MMOcancelled· E
    MEZA, MARTIN RTXgranted 2008-05-09cancelled 2009-03-10
  2. KC0ZGAcancelled· G
    Meza, Martin RCOgranted 2007-01-08cancelled 2008-05-09

Successor callsigns

Callsigns held now by people who previously held K5MMO.

  1. WA5UNIactive· E
    MEZA, MARTIN RTXgranted 2025-06-24
  2. W5MMFexpired· A
    DU BOIS, RALPH MOKgranted 2006-01-19cancelled 2018-01-20

All historical holders

Every license row we've seen with the callsign K5MMO, oldest first.

  • DU BOIS, RALPH M OK
    1998-05-04 → cancelled 2006-01-19
  • MEZA, MARTIN R TX
    2018-12-28 → cancelled 2025-06-24
← Back to K5MMO License history →