Today was a weights & measures day – finding out how long batteries last, and how much parts weigh.<\/p>\n
Stills Camera<\/strong><\/p>\n Installed the CHDK firmware on the Canon IXUS camera, modified it to use less power, and tested that with a cat as the (very still) target! \u00a0This confirmed that the tiny internal battery won’t be enough, so I ordered a 3xAA holder to mount external batteries. \u00a0Tried different sizes of SD card and settled on a 2GB card which will be enough for the 2.5-3 hours in the air. \u00a0Found some gotchas and completed this part of the launch procedure.<\/p>\n Video Camera<\/strong><\/p>\n <\/strong>Tested the Kodak video camera with alkaline batteries (useless!) so that just confirmed that I’ll need to use Lithium cells. \u00a0Calculated how much time the 16GB SD card will give (again, enough for the expected flight time).<\/p>\n Weights<\/strong><\/p>\n Created a spreadsheet with the component weights. \u00a0Total (a bit of a guess till the case is made and some other parts are in) is 900g. \u00a0I have no doubt that will increase so I’m assuming 1kg total. \u00a0With 3.3 cubic metres of helium in a 1000g balloon that will give us a burst altitude of about 31km reached in about 2 hours. \u00a0With the return journey taking 30-40 minutes, this fits in nicely with the camera and video limits of about 3.5 hours.<\/p>\n Purchasing<\/strong><\/p>\n Today I ordered the Lithium AA cells, the radio downlink transmitter, polystyrene sheet\/glue\/cutter for the capsule, and the balloon itself! \u00a0The main item remaining is the helium gas, but that can wait till much closer to the launch date.<\/p>\n","protected":false},"excerpt":{"rendered":" Today was a weights & measures day – finding out how long batteries last, and how much parts weigh. Stills Camera Installed the CHDK firmware on the Canon IXUS camera, modified it to use less power, and tested that with a cat as the (very still) target! \u00a0This confirmed that […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[4],"tags":[],"_links":{"self":[{"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/posts\/12"}],"collection":[{"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=12"}],"version-history":[{"count":3,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/posts\/12\/revisions"}],"predecessor-version":[{"id":14,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=\/wp\/v2\/posts\/12\/revisions\/14"}],"wp:attachment":[{"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.daveakerman.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}