Re: LF: Octo-soundcard for the Raspi, another question

[DK7FC <selberdenken@posteo.de>]

Here it is: www.iup.uni-heidelberg.de/schaefer_vlf/VLF/test.vt

73, Stefan

Am 09.07.2017 19:33, schrieb Paul Nicholson:
> Let's try an experiment.
>
> Capture a short sample 6 channels 96k/sec int2 format,
> directly into a file.
>
> No input, all inputs open circuit. Max alsamixer gain.
>
> Hopefully capture where at least one channel is showing
> a long 'event', eg 100mS where the noise drops.
>
> Maybe it doesn't appear when there is no input tone.
>
> If it does, we can measure the noise during the event
> and compare with my Octo.  We can work out whether or not
> the noise level during the event is the 'correct' one.
>
>  vtcard -d hw:0,0 -b32 -c8 -r96000 -u -v test.vt,i2
>
> -u turns off timestamping.   Just ctrl-C to stop it
> after 20 seconds or so then look at it with vtsgram
> to see if any of the channels has a good noise event.
>
> --
> Paul Nicholson
> --