torsdag den 5. september 2019

Connecting fldigi to a WebSDR

This post explains how I connected Fldigi to a WebSDR on a Windows 10 computer.


Fig. 1. Goonhilly logo.

Qatar-OSCAR 100 Narrowband WebSDR is an excellent receiver! It is located at Goonhilly Earth Station in Cornwall, England. This WebSDR offers different modes, variable bandwidth, fine tuning, waterfall display, spectrum display, zoom function, and so on. Why not use this WebSDR for receiving digital signals from the QO-100 satellite and decoding them in fldigi?


Fig. 2. Fldigi desktop icon.

Fldigi is the leading application in digimode. It offers a multitude of digital protocols, from CW and RTTY over PSK31 to DominoEX, Olivia, THOR, and many more. Fldigi was written by W1HJK and is maintained by him and his team. Fldigi is a digital swiss army knife!

Step 1. Enable Stereo Mix on your Windows 10 computer. This link explains how to do it:
https://www.howtogeek.com/howto/39532/how-to-enable-stereo-mix-in-windows-7-to-record-audio/


Fig. 3. Sound window.

The Sound window is here: Control Panel > Hardware and Sound > Sound

Fig. 3 shows how Stereo Mix is enabled on my Windows 10 Home computer. A music video is playing in a browser window, and the audio moves the green bar up and down. The audio level is set to 100%.

Step 2. Select "Stereo Mix" as input source in the fldigi configuration window. The input source is called "Capture" in fldigi.  


Fig. 4. Configuration window in fldigi.

Fig. 4 shows how Stereo Mix is selected in the fldigi configuration window. The configuration window is opened by selecting Configure > Sound Card.

Fldigi can now receive audio from a webSDR or another sound source.You can test the function by playing a music video in a browser, and the fldigi waterfall will look like fig. 5!


Fig 5. Audio stream displayed in fldigi



Fig. 6. MFSK16 transmission from PA1SDB received by Fldigi.


Vy 73, OZ1BXM Lars
Webpage: oz1bxm.dk

tirsdag den 3. september 2019

Help - fldigi won't start

Fldigi is the leading application in digimode. It offers a multitude of digital protocols, from CW and RTTY over PSK31 to DominoEX, Olivia, THOR, and many more. Fldigi was written by W1HJK and is maintained by him and his team. Fldigi is a digital swiss army knife!

Having installed fldigi on Windows 10 Home, I executed the setup wizard and typed call, QTH, locator, and other details.


Fig. 1. Short-cut on Windows desktop.

The next day, I double-clicked the fldigi short-cut on my desktop (Fig. 1). Nothing happened. I did it again, but still no response from fldigi. PC rebooted. Nothing. Cleaned the Windows registry with Glary Utilities. Nothing. Uninstalled fldigi, rebooted the PC, and installed fldigi again. Still no action.

The solution came from WO9B in this blog post. One or more files in folder fldigi.files are corrupt. Here is what to do:

  1. Rename c:\users\oz1bx\fldigi.files to c:\users\oz1bx\fldigi-old.files
  2. Restart fldigi. 
  3. Fldigi will discover, that fldigi.files is missing, and it creates a new one. 
Setup data must be typed again. Move important files from fldigi-old.files to fldigi.files

Vy 73, OZ1BXM
Webpage: oz1bxm.dk