<html><body><span style="font-family:Verdana; color:#000000; font-size:10pt;"><div>At the risk of being a debbie downer, I would ask what is gained by adding voice to APRS? On the internet side of the equation I do see the value of some value to his, and there probably isn't any real down side; but as Bob pointed out there is a number of ways to talk VoIP already. Multitasking OS's give us the means to run several programs at once, letting someone do APRS-IS as well as Echolink and DStar all at once.<br></div><div><br></div><div>On the radio side of APRS, I see the potential for problems. I believe adding voice data could potentially add a lot of data being sent, which could prevent the usual stream of data from moving properly. My interest in APRS came about from my involvement with emergency communications. Our area has well defined voice channels set up, but we only use a single channel for APRS. The frequencies used for voice are organized in such a way to prevent problems with too much chatter. Currently, there isn't a problem getting the APRS data, but adding voice to the mix could change that if everyone were to begin talking over the APRS channel. <br></div><div><br></div><div>Frankly, given the amount of bandwidth devoted to voice over VHF, I don't see the advantage of having a voice-over-APRS.</div><div><br></div><div>Best Regards,</div><div>Mike Goldweber</div><div>KB3IXO<br></div><div><br></div><div> <br></div>
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Subject: [aprssig] APRS Voice links?<br>
From: Robert Bruninga <<a href="mailto:bruninga@usna.edu">bruninga@usna.edu</a>><br>
Date: Sun, May 19, 2013 1:08 pm<br>
To: <a href="mailto:aprssig@tapr.org">aprssig@tapr.org</a><br>
Cc: <a href="mailto:aprs@yahoogroups.com">aprs@yahoogroups.com</a><br>
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</style><div class="WordSection1"><div class="MsoPlainText">At Dayton there was a lot of excitement about FREE Digital Voice (FreeDV)</div><div class="MsoPlainText"> </div> <div class="MsoPlainText">Although it is currently being applied to robust HF communications at about 1200 baud in a 3 KHz channel, the basic Vocoder works at about 1000 baud or as low as 800 bits if the data stream is error protected. (Ie inside an AX.25 connected packet).</div> <div class="MsoPlainText"> </div><div class="MsoPlainText">At the risk of exposing my ignorance, I wonder how close we could get to relaying the raw Vocoder over an AX.25 link using our existing 9600 baud modems built into the Kenwoods? Even with the slow TXD delays (500 ms!) in Kenwood 9600 baud modems, a conversation could be continuous if the radio was transmitting this information at 9600 baud in packets once a second maybe...</div> <div class="MsoPlainText"> </div><div class="MsoPlainText">This would give experimenters a chance to see what we can do with Digital Voice using existing AX.25 links.</div><div class="MsoPlainText"> </div><div class="MsoPlainText">I have no idea what a network would look like, but if IGates could receive these 9600 baud connections, then it would seem like we could cobble together some kind of A-STAR system where we use the frton panel controls and APRS to set up who we want to talk to and then the IGates link us between any two hams anywhewre on the planet along with their APRS traffic.</div> <div class="MsoPlainText"> </div><div class="MsoPlainText">Anyway, a whole new exciting area to think about. Remember, it has always been my goal to have callsign-to-callsign voice contact (using APRS connectivity to set up the call). At first I thought IRLP, then Echolink, then ALL-STARR would be the answere. Then D-star actally is now doing it, and we still have not gotten organized to simply take what we have and do it too. See <a target="_blank" href="http://aprs.org/avrs.html">http://aprs.org/avrs.html</a></div> <div class="MsoPlainText"> </div><div class="MsoPlainText">Maybe this new FreeDV can serve as a spark for some new thinking…</div><div class="MsoPlainText"> </div><div class="MsoPlainText">Bob, Wb4APR</div><div class="MsoPlainText"> </div></div> <hr>_______________________________________________<br>
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