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

W0JU callsign genealogy

Currently held by MALLBERG, ROGER 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 W0JU's current licensee, walking backwards.

  1. W0RVactive· E
    PEMBERTON SR, JERALD MMOgranted 2026-08-27
  2. K0IKZcancelled· E
    PEMBERTON SR, JERALD MMOgranted 2008-09-04cancelled 2016-11-22

Successor callsigns

Callsigns held now by people who previously held W0JU.

  1. W0RVcancelled· E
    MALLBERG, ROGER DMTgranted 2012-10-23cancelled 2014-11-01
  2. W0RVcancelled· E
    MALLBERG, ROGER DMTgranted 2008-09-23cancelled 2010-10-09
  3. W0RVcancelled· E
    MALLBERG, ROGER DNDgranted 2004-08-20cancelled 2006-09-06

All historical holders

Every license row we've seen with the callsign W0JU, oldest first.

  • MALLBERG, ROGER D ND
    1999-04-08 → cancelled 2004-08-20
  • MALLBERG, ROGER D MT
    2006-09-06 → cancelled 2008-09-23
  • MALLBERG, ROGER D MT
    2010-10-09 → cancelled 2012-10-23
  • MALLBERG, ROGER D MT
    2014-11-01 active
← Back to W0JU License history →