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

N6COB callsign genealogy

Currently held by OBrien, Christopher E

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 N6COB's current licensee, walking backwards.

  1. K6BVZcancelled· G
    OBrien, Christopher ECAgranted 2018-08-07cancelled 2018-10-05
  2. KM6UQQcancelled· T
    OBrien, Christopher ECAgranted 2018-07-19cancelled 2018-08-07

Successor callsigns

Callsigns held now by people who previously held N6COB.

  1. KI6RKcancelled· E
    OBrien, Christopher ECAgranted 2022-07-15cancelled 2026-07-28

All historical holders

Every license row we've seen with the callsign N6COB, oldest first.

  • MARTIN, MARVIN G AZ
    1996-05-08 → cancelled 2008-05-09
  • OBrien, Christopher E CA
    2018-10-05 → cancelled 2022-07-15