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

KX4FB callsign genealogy

Currently held by O BRIEN III, JAMES V

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 KX4FB's current licensee, walking backwards.

  1. W4AMPactive· E
    O BRIEN III, JAMES VGAgranted 2017-09-08

Successor callsigns

Callsigns held now by people who previously held KX4FB.

  1. W4AMPactive· E
    O BRIEN III, JAMES VGAgranted 2017-09-08
← Back to KX4FB License history →