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

KX4IS callsign genealogy

Currently held by O Neill, Carlos 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 KX4IS's current licensee, walking backwards.

  1. KN4JUIcancelled· E
    O Neill, Carlos RTNgranted 2017-07-07cancelled 2018-02-16
  2. KK4CROcancelled· G
    O Neill, Carlos RTNgranted 2017-07-07cancelled 2018-02-16
  3. KN4EACcancelled· T
    O Neill, Carlos RTNgranted 2017-06-16cancelled 2017-07-07

Successor callsigns

Callsigns held now by people who previously held KX4IS.

  1. KB4COcancelled· E
    O Neill, Carlos RTNgranted 2018-03-06cancelled 2024-10-04
← Back to KX4IS License history →