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

AB1FF callsign genealogy

Currently held by SEFRANEK, THOMAS C

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 AB1FF's current licensee, walking backwards.

  1. WA1RHPcancelled· E
    SEFRANEK, THOMAS CMAgranted 2008-02-13cancelled 2017-08-11

Successor callsigns

Callsigns held now by people who previously held AB1FF.

  1. W1JPactive· E
    Pellant, Jon RFLgranted 2016-06-16

All historical holders

Every license row we've seen with the callsign AB1FF, oldest first.

  • Pellant, Jon R MA
    2004-08-19 → cancelled 2006-09-12
  • SEFRANEK, THOMAS C MA
    2017-08-11 active