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I haven't the sophisticated knowledge of how the DRAWS & UDRC perform their magic but I have the following observations.
Out of the box, the DRAWS would not work with my Yaesu 857D when running fldigi. I believe that the PTT wasn't working immediately after I did the initial configuration of fldigi but I can't be sure. Thinking back a couple years or so when I first got my first UDRC I began to suspect the ALSA settings. Examining the UDRC settings and comparing them to the DRAWS I tried changing a couple of the parameters on the DRAWS to correspond to those on the UDRC. After a couple changing a single parameter at a time with no change in outcome.
I realized that on the UDRC I had the on board audio turned on. In order to model the working UDRC, I decided to activate the onboard audio using the "dtparam=audio=on" parameter in the /boot/config.txt file on the DRAWS. I had no definite rationale for doing this other than to eliminate another difference in the UDRC and DRAWS configurations. The impact of making that change in situ on the DRAWS was disastrous as on a reboot the system was entirely un-useable. I immediately reversed that change and returned to pursuing the ALSA settings.
As my earlier approach of changing single ALSA parameters had not yielded any change in fldigi's performance, I did a wholesale change of the DRAWS alsa settings to those that were currently in place on my working UDRC. After completing these changes, the DRAWS was able to transmit and receive. There are still some issues though.
First, there is a significant difference in SNR reports on the UDRC vs the DRAWS. DRAWS levels appear to be 10 or more DB lower than those being reported by fldigi on the UDRC. As all I do to obtain these observations is move the 6-pin DIN connector back and forth between the UDRC and DRAWS using identical ALSA settings, I'd like to know what might be causing the differences in the SNR reports between those devices.
Another difference, which I note between the DRAWS and UDRC which may well be related to the level differences is in the fldigi waterfall display. To the best of my knowledge the applicable waterfall settings on the DRAWS and the UDRC but the displays are significantly different. I've got my UDRC set so that the waterfall shows a constant noise level. Lots of others seem to prefer having a noiseless screen that only display's stronger signals. I find that by leaving the display set so that it displays noise I am able to visually identify some weak FSQ signal patterns.
I'd also like to know what it takes to get the on board audio working on the DRAWS after all some of the software running on the DRAWS provides audio cues that it might be nice to use. Of course assuming that those cues can be delivered to the on board audio for presentation.
I want to applaud all of NWDR's efforts at bringing us some very cool and useful tools. I also recognize that providing documentary support for these tool is extremely challenging given the resources available. Given the constraints, I know that it is a lot to expect that NDWR keep in mind that we users including early adopters often don't have the necessary depth of knowledge that NDWR folks have and expecting us to know about non-standard applications (e.g. chrony vs ntp) or even basic linux system operations need to be carefully considered assumptions.
Finally, I'd like to find out if NWDR has any ideas why I'd be seeing the differences in SNR that appear between the DRAWS and UDRC? What have I overlooked or just don't know about?
Thanks again for your time and attention.
On Wed, Dec 19, 2018 at 7:07 AM Jack Spitznagel <kd4iz@...> wrote:
Basil, John, All,