The problem is that the "smearing" is additive. The transmitter adds some, the ionsphere adds more, then the receiver even more. In order to maximize the phase coherence, the ionsphere should be the only contributor. I recognize that economic costs may impact this. But again, I just wanted to point out that dealing with the computer side, i.e. modem, is only one part of the system. --- In digitalradio@yahoogroups.com, KV9U <[EMAIL PROTECTED]> wrote: > However, I think that the ionosphere is > even worse than most amateur equipment. > > Here is a URL that helps explain it: > > http://www.rfengineer.cc/pdf/group_delay.pdf > > 73, > > Rick, KV9U > > > DuBose Walt Civ AETC CONS/LGCA wrote: > > >Rick, > > > >Please explain "group delays". I am unfamilar with that term in reference to transmitting equipment. > > > >Walt/K5YFW > > > >-----Original Message----- > >From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] > >Sent: Wednesday, September 20, 2006 4:28 PM > > > >[stuff deleted] > > > >Another thing that I came across in my web searching was that amateur > >equipment generally has group delays that make it difficult to even > >employ some of the modems we have been discussing. > > > >I wonder if any of the modem experts might comment on that. > > > >73, > > > >Rick, KV9U > > > > > > > > >
Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
