WSPRLINUX with SDR Receiver:
this information was provided by ON4CDJ:
SDR receivers provide an I/Q signal which must be processed before it can be feed into varios HAM radio software.
A usual way is to use snd-aloop from Linrad. This processes the I/Q signal from the SDR and generates a sound signal which can be used by wsprlinux. This sound signal is available as a virtual sound card, a loopback-device.
We need to tell wsprlinux how to access this device.
wsprlinux does not read from the soundcard directly, instead it uses the linux tool "arecord" to capture the sound card. We need to tell arecord where to find our loopback device. This can be done with the command line option -Dplughw:2,1. Where 2 and 1 depend on the number of soundcards installed in your system.
We can run arecord manually from the command line to test if the command line option is working. When it is working we enter this option in wsprlinux in the Setup windows in "Sound recording options".
Now wsprlinux can read the sound from your SDR receiver.