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

N1RIU 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 N1RIU's current licensee, walking backwards.

  1. KC1BQIcancelled· T
    Krystofolski, Jeffrey WCTgranted 2014-04-21cancelled 2014-05-13

Successor callsigns

Callsigns held now by people who previously held N1RIU.

  1. N4RIUactive· E
    KRYSTOFOLSKI, JEFFREY WFLgranted 2020-04-28

All historical holders

Every license row we've seen with the callsign N1RIU, oldest first.

  • KRYSTOFOLSKI, JEFFREY W CT
    1994-02-08 → cancelled 2006-02-09
  • KRYSTOFOLSKI, JEFFREY W FL
    2014-05-13 → cancelled 2020-04-28