KC3KOS
Active2x3District 3
Competitive callsign — 1 application filed with the FCC.
License HolderSTERNTHAL, JONATHAN W
License ClassGeneral
Min. Class RequiredTechnician
LocationWarren, OH
Grant DateDec 12, 2025
Expiration DateDec 12, 2035
KC3KOS is a highly sought-after 2x3 format amateur radio callsign. The license is currently held by STERNTHAL, JONATHAN W in Warren, OH. 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 STERNTHAL, JONATHAN W on Nov 24, 2025. KC3KOS has 6 recorded FCC license history events.
CW & Voice Analysis
Morse Code
-.- -.-. ...-- -.- --- ...
CW Weight: 43 units(Heavy (slower to send))
Voice Phonetics
Kilo Charlie Three Kilo Oscar Sierra
Readability: 7/10(Good readability)
License History
- Administrative Update AppliedDec 24, 2025
- License IssuedDec 12, 2025
- Vanity Callsign GrantedDec 12, 2025
- License CanceledFeb 16, 2018
- System-Generated GrantJan 12, 2018
- License IssuedJan 12, 2018
Vanity Application Activity
Competing applications filed with the FCC for this callsign.
- STERNTHAL, JONATHAN WFiled Nov 24, 2025Not awardedFCC ↗