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NI4O

Active2x1District 4

Competitive callsign — 1 application filed with the FCC.

License HolderStewart, Mary J

License ClassAmateur Extra

Min. Class RequiredAmateur Extra

LocationO'BRIEN, FL

Grant DateJan 21, 2017

Expiration DateMar 17, 2027

NI4O is a highly sought-after 2x1 format amateur radio callsign. The license is currently held by Stewart, Mary J in O'BRIEN, FL. This callsign has attracted significant interest in the amateur radio community, with 1 vanity application filed with the FCC. The most recent was submitted by Stewart, Mary J on Feb 27, 2007. NI4O has 6 recorded FCC license history events.

CW & Voice Analysis

Morse Code

-. .. ....- ---

CW Weight: 22 units(Light (fast to send))

Voice Phonetics

November India Four Oscar

Readability: 7.5/10(High readability)

License History

License RenewedJan 21, 2017
Administrative Update AppliedNov 20, 2014
License IssuedMar 17, 2007
Vanity Callsign GrantedMar 17, 2007
Internal Correction AppliedMar 8, 2007
Internal Correction AppliedMar 8, 2007

Vanity Application Activity

Competing applications filed with the FCC for this callsign.

Stewart, Mary JFiled Feb 27, 2007
Not awardedFCC ↗

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FCC data as of Jul 28, 2026

NI4O FCC Vanity Status: 1 Competing Application & History