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

AB4BA callsign genealogy

Currently held by DUTTWEILER, MARK 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 AB4BA's current licensee, walking backwards.

  1. KE0SYJcancelled· E
    MCDOWELL, BRAD CCOgranted 2018-09-07cancelled 2019-03-29

Successor callsigns

Callsigns held now by people who previously held AB4BA.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign AB4BA, oldest first.

  • DUTTWEILER, MARK D FL
    2007-02-07 → cancelled 2019-02-12
  • MCDOWELL, BRAD C CO
    2019-03-29 active