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<DIV><FONT face=Arial size=2>Hey Guys,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I've got a question, not about an aircraft
altimeter, but one I'm thinking of building for model rocket use.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>For those of you into the hobby, you know that even
the most basic altimeter good for data logging and, most importantly to me,
ejection charge timing, can be very expensive (cheapest I've found to do what I
need is about $120). But I've found what seems to be a very nice setup
online, here:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2><A
href="http://www.rocket-roar.com/rap/alt.html">http://www.rocket-roar.com/rap/alt.html</A></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm confident I could build this altimeter and get
it working, I know enough to do that, but I'm not quite experienced enough to
modify it to what I need it to do (blow an ejection charge). This setup is just
a data-logger. What I need is for it to trip a relay at some pre-specified
altitude or time after apogee which would blow the ejection charge. This is
pretty important, because the launchsite we use up here is very narrow, flanked
by a dense forrest on one side and Lake Superior on the other. It's nice and
long, but if you drift to the side you're screwed! I lost two rockets to the
trees on our last launch, and I would have lost my prized V2 to the Lake had the
parachutes not come off on the last flight (thats a funny story in and of itself
- I'll tell it later ;) </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So anyway, long story short, anyone here have
experience with PICs and whatnot, who could take a look at the circuit and code
and give me some ideas on modding it to trip a relay? I'd be VERY appreciative!
:)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>If we can modify this circuit, it could be used for
all sorts of useful things, including staging. My mouth waters with the
possibilities! :)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Brian</FONT></DIV></BODY></HTML>