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

AF4MB callsign genealogy

Currently held by Williston, Frederick F

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 AF4MB's current licensee, walking backwards.

  1. AI4CPactive· E
    POPE, CHRISTOPHER MNCgranted 2018-04-17
  2. KI4SKVcancelled· E
    POPE, CHRISTOPHER MNCgranted 2016-10-25cancelled 2018-04-17

Successor callsigns

Callsigns held now by people who previously held AF4MB.

  1. AF4RFcancelled· E
    TRAIL, MATTHEW TNYgranted 2008-09-20cancelled 2018-10-01

All historical holders

Every license row we've seen with the callsign AF4MB, oldest first.

  • Williston, Frederick F SC
    2023-10-24 active
  • TRAIL, MATTHEW T
    — → cancelled 1998-10-27
← Back to AF4MB License history →