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

KI4FIO callsign genealogy

Currently held by SIMMONS, MICHAEL P

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 KI4FIO's current licensee, walking backwards.

  1. K4MPSactive· E
    Shields, Michael PFLgranted 2024-08-30
  2. KZ4JTcancelled· E
    Shields, Michael PFLgranted 2020-11-13cancelled 2024-08-30
  3. KO4JCWcancelled· E
    Shields, Michael PFLgranted 2020-11-13cancelled 2024-07-16

Successor callsigns

Callsigns held now by people who previously held KI4FIO.

  1. K4MPScancelled· T
    SIMMONS, MICHAEL PNCgranted 2004-06-11cancelled 2004-07-09

All historical holders

Every license row we've seen with the callsign KI4FIO, oldest first.

  • SIMMONS, MICHAEL P NC
    2004-04-28 → cancelled 2004-06-11
  • SIMMONS, MICHAEL P NC
    2025-03-19 active
← Back to KI4FIO License history →