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<div dir="ltr" data-setdir="false">Hello,</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Not much activity in this list recently. Since my previous email I have installed and successfully run the linux modem <a href="https://github.com/aicodix/modem/" rel="nofollow" target="_blank">https://github.com/aicodix/modem/</a> in a Raspberry version 1. I have left it up and working for several days. The script records sound clips from a 2 meter radio, demodulates the data, shows the message in an http server:<br></div><div dir="ltr" data-setdir="false"><a href="http://ea4gmz.hopto.org/OFDM.txt" rel="nofollow" target="_blank">http://ea4gmz.hopto.org/OFDM.txt</a><div dir="ltr" data-setdir="false">and repeats the same message a few seconds later. Fellow hams around Madrid have been able to exchange messages using Rattlegram in their smartphones and a fixed or handheld radio. It works through voice repeaters too. The modem software was modified for making the algorithm faster, maybe at the expense of some sensitivity. I have not noticed a significant loss of sensitivity, and now it takes less than 100 ms to process an audio clip and decode the message, even in a Rpi 1.<br></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">This is a temporary and experimental system. I wish to engage more people into Rattlegram as an introduction to Ribbit.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div><br></div><div><br></div><br></div><div><br></div>
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En miércoles, 7 de febrero de 2024, 23:25:23 CET, Ricardo Saiz <rsaizv@yahoo.es> escribió:
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<div><div id="yiv9113671237"><div><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;" class="yiv9113671237yahoo-style-wrap"><div dir="ltr">Hello</div><div dir="ltr">I have played a bit with the linux software <a rel="nofollow noopener noreferrer" target="_blank" href="https://github.com/aicodix/modem/">https://github.com/aicodix/modem/</a> and the Android app. I wrote my experiencies in my blog, currently in spanish only:</div><div dir="ltr"><a rel="nofollow noopener noreferrer" target="_blank" href="https://www.radiotecnia.es/rattlegram-experimentos-con-ofdm/" class="yiv9113671237">https://www.radiotecnia.es/rattlegram-experimentos-con-ofdm/</a></div><div dir="ltr"><a rel="nofollow noopener noreferrer" target="_blank" href="https://www.radiotecnia.es/digi-repetidor-rattlegram/">https://www.radiotecnia.es/digi-repetidor-rattlegram/</a></div><div dir="ltr">I modified YD1RUH's script for adding more information to the message log and also for repeating the received messages, so my station can act as a digipeater. This is a simple and very basic way of implementing some features that are announced for Ribbit. Looking forward to trying that app when it becomes available.<br></div><div dir="ltr">regards<br></div></div></div></div></div>
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