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Direction of audio streams from different receivers to individual sound cards?
Hello,
I am intending to use the KiwiSDR for an aeronautical HF/SSB monitoring project.
In its present configuration, the audio streams from all receivers are superimposed on one sound-card channel.
This is impractical when monitoring many channels simultaneously, as the noise from the idle channels will deteriorate the SNR of the active channel.
Is there a way of separating the audio streams to separate sound-card channels?
It is intended to use a web browser running on a Linux platform.
A related question is if there is some way to implement an adjustable RF gain threshold, so the background noise can be suppressed somewhat?
I am intending to use the KiwiSDR for an aeronautical HF/SSB monitoring project.
In its present configuration, the audio streams from all receivers are superimposed on one sound-card channel.
This is impractical when monitoring many channels simultaneously, as the noise from the idle channels will deteriorate the SNR of the active channel.
Is there a way of separating the audio streams to separate sound-card channels?
It is intended to use a web browser running on a Linux platform.
A related question is if there is some way to implement an adjustable RF gain threshold, so the background noise can be suppressed somewhat?
Comments
>A related question is if there is some way to implement an adjustable RF gain threshold, so the background noise can be suppressed somewhat?
>
Yes it can be adjusted in the purple tabbed AGC section of the control panel.
Regards,
Martin - G8JNJ
For Linux I use Pulse Audio and Pavucontrol to manage audio streams.
https://wiki.archlinux.org/index.php/PulseAudio
https://wiki.archlinux.org/index.php/PulseAudio/Examples
from the command line:
man pulseaudio
pacmd --help
pactl --help
Example window using Pavucontrol with Pulseaudio to direct audio streams from open tabs on a web browser.
Ron
KA7U
https://blackcatsystems.com/software/kiwiSdr-sound-client-virtual-audio-device.html
You can then feed a multitrack recorder or multiple soundcards.
As to the receiver gains, I get good results by reducing the AGC threshold until the noise floor is down to -15 dB. For the slope, try 2 dB instead of 6 for a bit better sound. Otherwise, the background noise will drive you mad, and recordings will be far more noisy than they need to be.
Some of the SDRs run with the gain way to high! Others don't, do definitely take the time to adjust each channel as necessary.
Cheers,
Phil AB9IL
I've learned the hard way to steer clear of PulseAudio. If it works for you, fantastic. Doesn't work right for me.