--- In digitalradio@yahoogroups.com, "DuBose Walt Civ AETC CONS/LGCA" <[EMAIL PROTECTED]> wrote: > > I've heard DV using LCP-10 and a 16 tone modem as well as a 39 tone modem at 1200 bps...it sounds robotic at best. But that could have been just the systems used (ANDVT/Mil-STD-188-110) > > Walt/K5YFW
Walt, Thanks for your very interesting and informative comments. I would be very interested in meeting you on the air for an extended conversation on the subject. We should be able to connect on 40M or 80M in the evenings. I often monitor 7295 +/-. I can also be reached on EchoLink. Some of the questions I have are: 1) Can you suggest a reference on HF propagation that may show distributions or histograms of fade depths, durations and bandwidths? 2) For the examples of military equipment you gave, did they use voice bandwidths (~2.5 KHz) or were the bandwidths larger? 3) With military communications I expect that voice quality and accuracy of the communication is essential. For ham weak signal applications where accuracy is not a life and death matter, can we gain any performance by trading codec data for FEC data? If voice quality at 2400 bps is considered acceptable for military applications, can we get better SNR performance with useable voice quality for ham applications at codec data rates less than 2400 bps with stronger FEC? Is there anyone reading this thread that could develop additional experimental modes for WinDRM? Ed WB6YTE 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/
