<div>Tweeks,</div><div> </div><div>I really like your ejection charge holder idea and am very interested to see how that works. I had to attempt level 2 3 times because, in part, I had issues orienting the ejection charges (Robbies flashbulbs in cardboard tubes) so they didn't blow a hole in my cardboard airframe. You have an elegant solution for making sure it fires up. Eventually I found out that tubes weren't required, a corner of a baggie works just fine and is less directionally focused. </div>
<div> </div><div>As far as altimeter arming, I think I've tried just about everything there is - and I've never had a problem. I started with 1/4" phono plugs making sure the contacts were oriented so they were perpendicular to expected G forces.</div>
<div> </div><div>I've also used the twist wire method without any problems. I wrapped the exposed wire with masking tape and pushed it into one of the barometric ports. Later I would just use masking tape and taped the ends to the body just below the port.</div>
<div> </div><div>Now I prefer the Aerocon rotary voltage select switch in my 3" airframes. For 4" and larger I use a remove before flight pull pin/flag to safe and arm the electronics. Unfortunately I have all of them mounted so I can't take pictures. I have some Visio drawings that I'll find and send to you. The basic idea is to use a brass tube with cut outs for micro roller switches wired to NC side. I stagger the switches so I can pull the pin about 1" and arm one altimeter first, listen for the beeps and then arm the second.</div>
<div> </div><div>I like the visual reminder of the RBF flags and the geekiness of it. The rotary selector switch are probably the simplest and dependable. I haven't tried the screw switches, but they are probably another good choice.<br>
</div><div>Hope we can see it fly soon!</div><div> </div><div>Bob<br></div><div class="gmail_quote">On Wed, Jul 6, 2011 at 12:33 AM, Thomas Weeks <span dir="ltr"><<a href="mailto:tweeksjunk2@theweeks.org">tweeksjunk2@theweeks.org</a>></span> wrote:<br>
<blockquote style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;" class="gmail_quote"><u></u>
<div style="font-family: "Bitstream Vera Sans Mono"; font-size: 9pt; font-style: normal; font-weight: 400;">
<p style="margin: 0px; text-indent: 0px;">This is a question for you high power guys who have been shooting H and up birds for years.</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">Background:</p>
<p style="margin: 0px; text-indent: 0px;">-------------</p>
<p style="margin: 0px; text-indent: 0px;">So my first HP rocket is about ready to fly... and I plan on using it to get my L1 (H) and L2 (J) certifications. The L1 is no problem. Up, pop, float down. But as most of you know.. L2 certification also requires a written test (no problem) as well as "Active recovery", or a way of measuring your altitude and ejecting multiple chutes at precisely the right times to safely recover my rocket.</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">Well.. I've now mostly built my avionics bay, or "e-bay" and wired in a GWiz LCX flight computer:</p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1049573&l=3b9cc7e689&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1049573&l=3b9cc7e689&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1052820&l=fde4de7d63&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1052820&l=fde4de7d63&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1052821&l=8f9d1e56c2&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1052821&l=8f9d1e56c2&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1052825&l=878029acee&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1052825&l=878029acee&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1052823&l=079bcf0bff&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1052823&l=079bcf0bff&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.facebook.com/photo.php?pid=1052824&l=d39d643ca4&id=1844028171" target="_blank">http://www.facebook.com/photo.php?pid=1052824&l=d39d643ca4&id=1844028171</a></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">Here are some other pictures of other people's e-bay construction and products:</p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.vanderbilt.edu/USLI/2011/media.php?gallery=jan_19_2010" target="_blank">http://www.vanderbilt.edu/USLI/2011/media.php?gallery=jan_19_2010</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.apogeerockets.com/electronics_bays.asp" target="_blank">http://www.apogeerockets.com/electronics_bays.asp</a></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.rocketryplanet.com/content/view/2960/95/#axzz1RIL7aYxk" target="_blank">http://www.rocketryplanet.com/content/view/2960/95/#axzz1RIL7aYxk</a></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">My Question:</p>
<p style="margin: 0px; text-indent: 0px;">-------------</p>
<p style="margin: 0px; text-indent: 0px;">Anyway.. my question for Bob and other experienced Rocketeers..</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">What should I use for my flight computer's power safety switch?</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">So you're supposed to have a power arming safety circuit to ensure that your ejections charges don't blow before you launch the thing... They usually look something like this:</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://aeroconsystems.com/cart/products/RBF4-47-10.html" target="_blank">http://aeroconsystems.com/cart/products/RBF4-47-10.html</a></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">And are hung off something like a 1/8th " audio jack (where the normally closed circuit is open when the audio plug is in... and removing it completes (or closes) the circuit.. and powers up the computer). However.. I hear that the flight vibration can really make those switch contacts bounce around, which can reset the flight computer.. which leads to big expensive crashes. So a lot of folks use these high-G rated switches like this:</p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://aeroconsystems.com/cart/products/PCB_Screw_Switch-110-0.html" target="_blank">http://aeroconsystems.com/cart/products/PCB_Screw_Switch-110-0.html</a></p>
<p style="margin: 0px; text-indent: 0px;">or</p>
<p style="margin: 0px; text-indent: 0px;"><a href="http://www.aeroconsystems.com/electronics/switches.htm" target="_blank">http://www.aeroconsystems.com/electronics/switches.htm</a></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">Not nearly as cool/sexy as the "yank it out" audio plug that I want to use. :)</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">So what do you other HP folks recommend? Slide switches? Hard wired toggles? Audio jack/plugs?</p>
<p style="margin: 0px; text-indent: 0px;"></p>
<p style="margin: 0px; text-indent: 0px;">Tweeks</p></div><br>_______________________________________________<br>
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<br></blockquote></div><br>