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

W1MLO callsign genealogy

Currently held by Opsahl, Matthew

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 W1MLO's current licensee, walking backwards.

  1. KF0OQKcancelled· E
    Opsahl, MatthewNDgranted 2024-01-10cancelled 2024-03-09

Successor callsigns

Callsigns held now by people who previously held W1MLO.

  1. W0MLOactive· E
    Opsahl, Matthew LNDgranted 2024-04-09
  2. W8MLOexpired· T
    Oldaker, Mike LWVgranted 2012-02-24cancelled 2024-02-27

All historical holders

Every license row we've seen with the callsign W1MLO, oldest first.

  • Oldaker, Mike L WV
    2011-09-20 → cancelled 2012-02-24
  • Opsahl, Matthew ND
    2024-03-09 → cancelled 2024-04-09
← Back to W1MLO License history →