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K4CLS

Active1x3District 4

Competitive callsign — 1 application filed with the FCC.

License HolderSANTOS, CESAR RUSTY L

License ClassTechnician

Min. Class RequiredGeneral

LocationCARSON, CA

Grant DateNov 14, 2018

Expiration DateDec 1, 2028

K4CLS is a highly sought-after 1x3 format amateur radio callsign. The license is currently held by SANTOS, CESAR RUSTY L in CARSON, CA. 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 Surges, Ronald P on Apr 2, 2015. K4CLS has 3 recorded FCC license history events.

CW & Voice Analysis

Morse Code

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

CW Weight: 31 units(Moderate)

Voice Phonetics

Kilo Four Charlie Lima Sierra

Readability: 7.5/10(High readability)

License History

License RenewedNov 14, 2018
License RenewedOct 8, 2008
FRN Association Letter SentOct 7, 2008

Vanity Application Activity

Competing applications filed with the FCC for this callsign.

Surges, Ronald PFiled Apr 2, 2015
DismissedFCC ↗

Search external databases

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Explore nearby callsigns

← K4CLR K4CLT →

FCC data as of Sep 3, 2026

K4CLS FCC Vanity Status: 1 Competing Application & History