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

KC1AW callsign genealogy

Currently held by HOLBROOK, MARK D

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 KC1AW's current licensee, walking backwards.

  1. KC1AWWcancelled· E
    BACKHAUS, JOHN WNHgranted 2013-12-06cancelled 2021-11-30

Successor callsigns

Callsigns held now by people who previously held KC1AW.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign KC1AW, oldest first.

  • HOLBROOK, MARK D MA
    2006-05-16 → cancelled 2018-08-10
  • BACKHAUS, JOHN W NH
    2021-11-30 active