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Confidence: Medium · Source: FCC ULS · As of 2026-09-14

KK7SX callsign genealogy

Currently held by JOHNSTON, 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 KK7SX's current licensee, walking backwards.

  1. WB7VQXcancelled· E
    Swann, Roger CWAgranted 2014-04-22cancelled 2020-04-17

Successor callsigns

Callsigns held now by people who previously held KK7SX.

  1. AC7AZactive· E
    JOHNSTON, MARK DAZgranted 2018-01-11

All historical holders

Every license row we've seen with the callsign KK7SX, oldest first.

  • Swann, Roger C WA
    2020-04-17 active
  • JOHNSTON, MARK D
    → cancelled 1999-05-13