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

N5MJK callsign genealogy

Currently held by KIEFER, MICHAEL J

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 N5MJK's current licensee, walking backwards.

  1. KB3QKFcancelled· E
    KIEFER, MICHAEL JTXgranted 2016-06-07cancelled 2017-11-28
  2. KB9NUXcancelled· G
    Kiefer, Michael JDEgranted 2006-05-18cancelled 2008-02-15

Successor callsigns

Callsigns held now by people who previously held N5MJK.

  1. W6EZUcancelled· E
    KAZMIERCZAK, MICHAEL JOKgranted 2011-06-29cancelled 2014-03-28

All historical holders

Every license row we've seen with the callsign N5MJK, oldest first.

  • CREAGER, STEVEN D OK
    1988-04-12 → cancelled 2000-04-13
  • KAZMIERCZAK, MICHAEL J OK
    2011-06-07 → cancelled 2011-06-29
  • KIEFER, MICHAEL J TX
    2017-11-28 active
← Back to N5MJK License history →