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

KD4MAS callsign genealogy

Currently held by SINK, MICHAEL A

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 KD4MAS's current licensee, walking backwards.

  1. KD4TPEcancelled· T
    SINK, MICHAEL ANCgranted 2012-07-30cancelled 2019-10-04

Successor callsigns

Callsigns held now by people who previously held KD4MAS.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KD4MAS, oldest first.

  • MORRIS, THOMAS D FL
    1992-03-31 → cancelled 2004-04-01
  • SINK, MICHAEL A NC
    2019-10-04 active