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 -----Original Message----- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] Sent: Wednesday, October 11, 2006 8:20 AM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Re: Digital Voice: Some thoughts after one week. It was my understanding that the QAM-4 modulation was used for the text transmission and you needed to use at least QAM-16 for the voice. How many bps can you get through with QAM-4? If LPC doesn't work at 1200 bps, then what other codec do you suggest? Even MELP (which is a type of LPC) normally was based upon a 2400 bps speed was it not? And apparently it works OK at 1000 bps? 73, Rick, KV9U cesco12342000 wrote: > >A codec withh 1000bit/sec would allow qam-4 modulation, and improve >the robustness to "useful" levels. Tests with a 1200 bit/sec LPC >codec have been negative (bad intellegibility). > > > > 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 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/
