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

KK4CRO 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 KK4CRO's current licensee, walking backwards.

  1. KN4EACcancelled· T
    O Neill, Carlos RTNgranted 2017-06-16cancelled 2017-07-07

Successor callsigns

Callsigns held now by people who previously held KK4CRO.

  1. WA4PODactive· G
    Smith, Douglas PSCgranted 2023-09-30
  2. KN4JUIcancelled· E
    O Neill, Carlos RTNgranted 2017-07-07cancelled 2018-02-16

All historical holders

Every license row we've seen with the callsign KK4CRO, oldest first.

  • Smith, J Douglas SC
    2011-06-16 → cancelled 2013-05-10
  • O Neill, Carlos R TN
    2017-07-07 → cancelled 2018-02-16
← Back to KK4CRO License history →