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

K1STX callsign genealogy

Currently held by Upton, Louis R

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 K1STX's current licensee, walking backwards.

  1. KB1ZQIcancelled· T
    Craig, Jeffrey SMEgranted 2013-04-04cancelled 2017-05-05

Successor callsigns

Callsigns held now by people who previously held K1STX.

  1. K5STXactive· G
    Upton, Louis RTXgranted 2020-06-13

All historical holders

Every license row we've seen with the callsign K1STX, oldest first.

  • Upton, Louis R TX
    2007-10-10 → cancelled 2010-08-06
  • Craig, Jeffrey S ME
    2017-05-05 active