<font face="arial" size="2"><p style="margin:0;padding:0;font-family: arial; font-size: 10pt;">Just looking at the pictures.</p>
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<p style="margin:0;padding:0;"><span style="font-family: arial; font-size: 10pt;">I went a different way for the payload. I had a rigid blue foam 'box' with Aluminium foil stuck to the outside using spray adhesive. Seemed to the the lightest way to get a box that wouldn't freeze, and the tinfoil made it look cool. :-)</span></p>
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<p style="margin:0;padding:0;"><span style="font-family: arial; font-size: 10pt;">On your slow ascent and bearing in mind this is from vague memory.. I think I needed an 8ft diameter balloon to lift 750gm fast enough to guarantee not getting into controlled airspace launching from up near Springfield. I found a rate of ascent vs payload vs air temp vs gas volume vs burst height formula somewhere on the web.</span></p>
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<p style="margin:0;padding:0;"><span style="font-family: arial; font-size: small;">Hmm, I'm gonna have to stop reading this. I already have waaaayyy to may projects on the go!</span></p>
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<p style="margin:0;padding:0;"><span style="font-family: arial; font-size: 10pt;">Cheers, Chris H.</span></p>
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<p style="margin:0;padding:0;font-family: arial; font-size: 10pt;">-----Original Message-----<br />From: "André Geldenhuis" <andre.geldenhuis@gmail.com><br />Sent: Tuesday, 8 January, 2013 23:34<br />To: "Christchurch Robotics" <chchrobotics@lists.linuxnut.co.nz><br />Subject: Re: [chbot] Sundays balloon-adventure, report please<br /><br /></p>
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<div class="gmail_quote">On Tue, Jan 8, 2013 at 9:25 PM, Chris Hellyar <span dir="ltr"><<a href="mailto:chris@trash.co.nz" target="_blank">chris@trash.co.nz</a>></span> wrote:<br />
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<div>900gm is good going for all that gear without getting very specialised, especially with two cameras in the mix.<br /><br /> Without digging out all my olds notes my weight budget was 750gm and the 3W TX which was the guts of a miniature handheld was about 80gm, so 80x the weight of your TX!! :-).<br /><br /> I was only planning one camera but at the time I was having problems finding a tracker/GPS that would work at high altitude and something else shiny caught my eye... I've still got the bits in a box somewhere.</div>
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<div><br />That's a good weight :) I really recommend the Venus GPS units, I really like them and they do work about 60f feet. There is also a high dynamics firmware available for them which I am keen to test out on a rocket some time.<br /><br />Andre</div>
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