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

KR3D callsign genealogy

Currently held by O KEEFE, MICHAEL F

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 KR3D's current licensee, walking backwards.

  1. KG4TKWcancelled· E
    ROYCE, RALPH RTNgranted 2002-05-20cancelled 2003-09-05

Successor callsigns

Callsigns held now by people who previously held KR3D.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KR3D, oldest first.

  • O KEEFE, MICHAEL F PA
    1993-01-05 → cancelled 2001-01-08
  • ROYCE, RALPH R TN
    2023-09-07 active