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Welcome to the KFS WebSDR, located six miles south of Half Moon Bay, California USA.

This facility was established by Craig, W6DRZ (sk) and is maintained by a group of local and remote volunteers. Technical descriptions, operating tips, and up-to-date propagation information may be found on the ABOUT page.

More information on the worldwide WebSDR project can be found on www.websdr.org. An outstanding alternate system in the Western USA is Northern Utah WebSDR, north of Salt Lake City. For HF reception from the East coast, use either NA5B WebSDR in Washington, DC. or the K3FEF WebSDR in Pennsylvania.

Possible AUDIO problems with the CHROME web browser

A recent update to the CHROME web browser seems to have resulted in audio issues with this WebSDR and other web sites that stream audio.  In the meantime, if you are having audio problems while using Chrome we suggest that you use a different browser such as Safari, Firefox or Opera until the issues with Chrome's audio are resolved.


Antenna issues at the KFS WebSDR:

26 July, 2026

Frequent users of this WebSDR have certainly noticed that it has recently been getting very deaf - only the stronger signals were visible.

Today, a site visit was done to investigate the issue and it was determined that RF signals from the main antenna - the TCI-530 Omni - are down by between 15 and 30dB (3-5 "S" units or more). As antenna maintenance is not within the purview of the investigator, this information has been passed along and it is hoped that the appropriate people will track down and resolve the issue with this antenna in the near future.

In the meantime, the WebSDR's feed was connected to the "SouthEast" antenna - a TCI-527B. While this antenna has a beam that primarily favors South America, it does a reasonable job of receiving signals from the continental United States: Anyway, this is the best of the available antennas to make the system usable until the TCI-530 Omni is back online.

Further details will be posted as they become available.


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View:
Allow keyboard:
j k ← →: freq down/up (+shift/ctrl/alt faster)
u l c a f: USB, LSB, CW, AM, FM
z Z: center/zoom waterfall
g: enter frequency
m: mute/unmute audio
s: toggle squelch

Frequency: kHz    VFO:  ?  
Enter frequency above, or tune by clicking/dragging/scrollwheel on the frequency scale. freq???
Mode:  ?      
   VFO:
Use the = kHz button to snap to the nearest kHz.

Clicking a band below will switch to the secondary KFS WebSDR server
     
Memories:
Memories are stored as cookies on your computer, not on the server.
Bandwidth:
?:   ? kHz @ -6dB; ? kHz @ -60dB.  Default BW in bold.
 USB CW RX: Check box, or put  ?usbcw  in the URL for USB CW reception.
  CW uses a center frequency of 750 Hz and LSB by default.

PassBand Tuning (PBT):
Use buttons to select BW/mode or drag passband edges on frequency scale. PBT/IF Shift by Weert Websdr.
Logbook:
Call of station that you hear:
Comments, if any:
Time, frequency, your name/call, and DXCC information are added automatically.
View the last 20 lines of the logbook, or the entire logbook (opens new tab/window).


[scale]
? dBm  Peak ? dBm  ?
 S-meter squelch:        
  
Volume:
Mute Squelch Notch1
Notch2 High Boost
 DSP Noise Reduction:
More info about Noise Reduction, Notch2 & High Boost here
Audio buffering:
  More buffering may help with drop-outs or slow/jittery connections.
  Vari-Notch (Hz):   Off
   CW Peak (Hz):   Off    Ref. Tone

Gain control:   
RF AGC Alt AGC Manual
Gain:
Try "Alt AGC" for better AM reception, particularly with QSB.
devpk dev_avg dev_pkavg   
Audio channel: Left Both Right
Sig. strength plot:
Waterfall view:
Or use scroll wheel & dragging on waterfall.
Speed:
Size:
View:

Toggle "Hide labels" if labels are missing.


?      compact view
Statistics:
Actual CPU utilization percentage is 1/4th of the value shown above.
? devpk dev_avg dev_pkavg freq???