uls-tracker
Sign in
Confidence: Medium · Source: FCC ULS · As of 2026-09-12

KA9TDX callsign genealogy

Currently held by JACOBSON, FRANK S

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 KA9TDX's current licensee, walking backwards.

  1. KJ7BTBcancelled· T
    Jacobson, Frank SWAgranted 2018-11-08cancelled 2018-12-04

Successor callsigns

Callsigns held now by people who previously held KA9TDX.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KA9TDX, oldest first.

  • JACOBSON, FRANK S WA
    1993-02-09 → cancelled 2005-02-10
  • Jacobson, Frank S FL
    2018-12-04 active