El 6/1/26 a las 17:28, Brian Buhrow escribió:
hello. /dev/audio resets the device parameters back to the defaults when a process closes it. /dev/sound holds the parameters between opens and closes of different processes. So, if you use /dev/sound3 instead of /dev/audio3, your audioctl commands will still be in effect when you read your incoming audio data. Hope that helps. -Brian
Thanks so much, Brian. I am going to investigate that. WSJTX does not offer to me "/dev/sound" devices, only "/dev/audio"
I do not why but now the 440 Hz tone prints right on the waterfall 440 Hz. But no FT8 decodes.
I am feeding the receiver with a signal generator now.It appears to be a noisy strange signal instead of a steady and unique straight vertical line that should correspond to a sine wave.
I will continue investigating. Now the sample rate seems to be ok but there will be a reason for no decodes. Perhaps the card samples at 44100 Hz but NetBSD resamples it to 48000 and "destroys" it in some way? It does not occur with the internal card because perhaps it works fine at 480000 and no resamping is needed?
"man audio" page says: ... ...The frequency conversion adapts the simplest way (interpolation method for upward, and simple thinning method for downward) due to restriction in kernel resources and processing time. It will work well in most case but don't expect excessive quality.
... ummm, I do not know if it could affect this delicate digital radio modes. Anyway, many tests today and I think I am becoming a bit crazy.Tomorrow I will test feeding the sound card directly with an audio tone instead of an RF tone into the receiver and see if I can confirm signal degradation.
Regards.