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

W9OI callsign genealogy

Currently held by CHILDERS, MICHAEL C

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 W9OI's current licensee, walking backwards.

  1. KB9QCYcancelled· E
    SHOEMAKER, CLIFFORD LILgranted 1998-04-10cancelled 2002-12-06

Successor callsigns

Callsigns held now by people who previously held W9OI.

  1. W9MCactive· E
    CHILDERS, MICHAEL CTXgranted 2020-09-17

All historical holders

Every license row we've seen with the callsign W9OI, oldest first.

  • CHILDERS, MICHAEL C WI
    2000-06-23 → cancelled 2000-11-17
  • Shoemaker 318, Cliff L IL
    2022-11-11 active