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<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>Gudday
</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>I have been the last
few weeks playing with low power tx modules and sending GPS
data.</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>Here are some
observations:-</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>1. OOK or on off
keying of the transmitter works ok but a logic 0 shud be TX on. 1200
baud </FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>2. Radiometrix
modules will do up to 64kb/s</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>3. Video sender
modules and audio is also another option.</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>In sending of data,
I found out the hard way you need </FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>1. Preamble to let
the rx settle</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>2. Manchester
encoding or bit ballanced transmissions.</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>Here is a photo of
the modules I am playing with.</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2><A
href="http://vk4tec.no-ip.org/rf_modules.jpg">http://vk4tec.no-ip.org/rf_modules.jpg</A></FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>The next challenge
is bit bash data transfer with manchester encoding and
decoding.</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2>Regards</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial size=2>Andrew Rich
</FONT></SPAN></DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=781491221-25052007><FONT face=Arial
size=2>VK4TEC</FONT></SPAN></DIV></BODY></HTML>