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QO-100 Web SDR for Linux


if installation and program start was done successfully, the WebSDR is running now, but it has to be configured to see QO100.

To do this, open this URL in the home network with a WebBrowser:

so for example:

the easiest way to find out the IP address of the Linux computer is on the Linux computer itself by typing in the terminal: ip a


at first you only see an empty spectrum. To set it up, click the SETUP button in the upper right corner and this window will open:


Please enter at least the following values (the others are optional):

  • LNB original crystal frequency … usually 25 MHz
  • LNB reference frequency … the clock frequency which is fed to the LNB. Usually this is 25 MHz (so 25000000). When using the Amsat DL downconverter it is 24 MHz (24000000). Sometimes one uses also a crooked frequency, which is entered here in Hz,
  • output frequency of an additional down mixer … If the WebSDR is not directly connected to the LNB, but to the output of an additional down mixer, you enter the output frequency of this mixer in MHz (the Hz digits are calculated automatically).

these were the most important settings, the other fields can be filled in if necessary, the explanation is on the screen.

Now click Save and EXIT.

the frequencies are now tuned correctly and the spectrum of QO100 appears:

the WebSDR is now set up, continue in chapter Operation.

en/qo100websdr/setup.txt · Last modified: 2021/12/10 15:47 by dj0abr