At 11:35 AM 8/18/2007, Peter G. Viscarola wrote: > > > >For digital modes, I am now using two separate computers: ... > > > >...The downside of this approach is that it requires converting the audio >data from digital format to analog and back to digital again... and all >the re-sampling and potential issues this implies.
I don't think this is significant in the real world. After that poor signal has made it through that messy chaotic ionosphere anything this simple conversion does to it is _very_ "small potatoes" in comparison. >Also, in terms of connecting the serial ports: Note that that there's >any guarantee that the programs at both ends will work properly via any >particular "null modem" cable ... Yabut - you work with it a few minutes and then it starts working. No big deal. I am doing exactly what the Flex-5000C users will be doing if they operate digimodes. Also the same as "conventional" radio users - for instance, my IC-756PRO3 interconnections were the same as what I am using now with the SDR-1000 if you think of my SDR computer as part of the "receiver system" BTW, the "hiccup" I referred to earlier may have been a difference in operating frequencies between VAC and my RTTY AFSK generator. Symptom was that I had an occasional character (maybe every 20th/25th character) garbled. I would not have known this if I had not actually listened to my transmissions on a second receiver on the desk. Anyone could be having this problem and not know it without direct listening - a listener 1000 miles away might not notice. Maybe I could have worked through this, but I didn't try. Direct cabling completely eliminated the hiccup. Bottom line - maybe direct digital conversion of the signal has downsides as well. Jerry W4UK _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
