KN4USB
Available2x3District 4
Competitive callsign — 2 applications filed with the FCC.
License HolderRosenberg, Michael I
License ClassGeneral
Min. Class RequiredTechnician
LocationVero Beach, FL
Grant DateMay 22, 2019
Expiration DateMay 22, 2029
Cancellation DateJul 20, 2019
Available for ApplicationsJul 21, 2021
KN4USB is a highly sought-after 2x3 format amateur radio callsign. The license is currently held by Rosenberg, Michael I in Vero Beach, FL. 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 Clark, Stephanie R on Jul 10, 2025. KN4USB has 6 recorded FCC license history events.
CW & Voice Analysis
Morse Code
-.- -. ....- ..- ... -...
CW Weight: 32 units(Moderate)
Voice Phonetics
Kilo November Four Uniform Sierra Bravo
Readability: 6/10(Good readability)
This callsign is available now
Requires Technician license or higher to apply for this callsign format (2x3).
License History
- License CanceledJul 20, 2019
- License ModifiedJun 25, 2019
- Administrative Update AppliedMay 25, 2019
- Administrative Update AppliedMay 25, 2019
- System-Generated GrantMay 22, 2019
- License IssuedMay 22, 2019
Vanity Application Activity
Competing applications filed with the FCC for this callsign.