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

N4RIU callsign genealogy

Currently held by KRYSTOFOLSKI, JEFFREY W

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 N4RIU's current licensee, walking backwards.

  1. N1RIUcancelled· E
    KRYSTOFOLSKI, JEFFREY WFLgranted 2014-05-13cancelled 2020-04-28
  2. KC1BQIcancelled· T
    Krystofolski, Jeffrey WCTgranted 2014-04-21cancelled 2014-05-13

Successor callsigns

Callsigns held now by people who previously held N4RIU.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign N4RIU, oldest first.

  • MC KEOWN, TIMOTHY A GA
    2009-01-29 → cancelled 2020-04-10
  • KRYSTOFOLSKI, JEFFREY W FL
    2020-04-28 active
← Back to N4RIU License history →