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

K4YZ callsign genealogy

Currently held by Killingsworth, Stephen L

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 K4YZ's current licensee, walking backwards.

  1. N4BQactive· E
    Thornton, RobertGAgranted 2022-07-23
  2. W9PRAcancelled· E
    Thornton, RobertGAgranted 2021-07-12cancelled 2022-07-23
  3. KO4PXPcancelled· E
    Thornton, RobertGAgranted 2021-04-30cancelled 2021-07-12

Successor callsigns

Callsigns held now by people who previously held K4YZ.

  1. K4CAPcancelled· E
    ROBESON, STEVEN JTNgranted 2003-05-13cancelled 2003-06-27

All historical holders

Every license row we've seen with the callsign K4YZ, oldest first.

  • ROBESON, STEVEN J TN
    1996-12-04 → cancelled 2003-05-13
  • ROBESON, STEVEN J TN
    2013-04-11 → cancelled 2018-06-14
  • Killingsworth, Stephen L FL
    2020-07-03 active
← Back to K4YZ License history →