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KU5X

Active2x1District 5

Competitive callsign — 2 applications filed with the FCC.

License HolderMason, Michael R

License ClassAmateur Extra

Min. Class RequiredAmateur Extra

LocationDenver, CO

Grant DateFeb 24, 2023

Expiration DateMay 2, 2033

KU5X is a highly sought-after 2x1 format amateur radio callsign. The license is currently held by Mason, Michael R in Denver, CO. This callsign has attracted significant interest in the amateur radio community, with 2 vanity applications filed with the FCC. The most recent was submitted by Mason, Michael R on Apr 14, 2003. KU5X has 5 recorded FCC license history events.

CW & Voice Analysis

Morse Code

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

CW Weight: 25 units(Light (fast to send))

Voice Phonetics

Kilo Uniform Five X-ray

Readability: 8/10(High readability)

License History

License RenewedFeb 24, 2023
License RenewedFeb 14, 2013
License IssuedMay 2, 2003
Vanity Callsign GrantedMay 2, 2003
License ExpiredMar 27, 2003

Vanity Application Activity

Competing applications filed with the FCC for this callsign.

Mason, Michael RFiled Apr 14, 2003
Not awardedFCC ↗
Riska, Robert DFiled Mar 26, 2003
Not awardedFCC ↗

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FCC data as of Sep 12, 2026

KU5X FCC Vanity Status: 2 Competing Applications & History