It seems Java is not installed or disabled on your computer. You need to install and/or enable it for this website to work properly.
Since Java version 7u51, Java needs to be enabled separately for each website; see http://websdr.org/java.html for instructions.
Your browser does not seem to support HTML5 WebAudio; please try a recent version of Firefox, Chrome, Opera or Safari; or switch to Java.
Use buttons to select BW/mode or drag passband edges on frequency scale. PBT/IF Shift by Weert Websdr.Logbook: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).
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.
devpkdev_avgdev_pkavg
Audio recording:
Recorded audio includes any DSP filtering, Notch2 or High Boost. Your browser may not support downloading the recording; Try it anyway, but if it doesn't work, please try a recent version of Firefox, Chrome or Opera.
Sig. strength plot:
Waterfall view:
Or use scroll wheel & dragging on waterfall.
Speed:
Size:
View:
Toggle "Hide labels" if labels are missing.
Statistics:
Actual CPU utilization percentage is 1/4th of the value shown above.