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Confidence: Medium · Source: FCC ULS · As of 2026-09-11

WA4SW callsign genealogy

Currently held by Butler, John M

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 WA4SW's current licensee, walking backwards.

  1. W4PSWcancelled· E
    Westbrook, Stephen JSCgranted 2021-10-26cancelled 2022-04-08
  2. KG4PSFcancelled· E
    Westbrook, Stephen JSCgranted 2021-08-20cancelled 2021-10-26

Successor callsigns

Callsigns held now by people who previously held WA4SW.

  1. K5OWGactive· E
    Butler, John MFLgranted 2022-06-14
  2. WA7CQcancelled· E
    WALKOWSKI, STANLEY ANVgranted 2016-07-29cancelled 2018-08-17
  3. AE8Fcancelled· E
    Butler, John MFLgranted 2010-12-17cancelled 2011-06-21

All historical holders

Every license row we've seen with the callsign WA4SW, oldest first.

  • Butler, John M FL
    2009-06-30 → cancelled 2010-12-17
  • Butler, John M FL
    2011-06-21 → cancelled 2011-12-13
  • WALKOWSKI, STANLEY A NV
    2015-03-17 → cancelled 2016-07-29
  • Westbrook, Stephen J SC
    2022-04-08 active
← Back to WA4SW License history →