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

KN4IO callsign genealogy

Currently held by HOLCOMB, WILLIAM H

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 KN4IO's current licensee, walking backwards.

  1. K4NIOcancelled· E
    HOLCOMB, WILLIAM HFLgranted 2000-06-09cancelled 2009-09-29
  2. KC4YTPcancelled· G
    HOLCOMB, WILLIAM HFLgranted 1996-08-14cancelled 2000-06-09

Successor callsigns

Callsigns held now by people who previously held KN4IO.

  1. AB4ZEexpired· E
    SPRENG, ROBERT VFLgranted 2000-07-08cancelled 2012-10-03
← Back to KN4IO License history →