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GPS Tracker Rev 3

For a little more information on the build process for this tracker, see the end of this post on 4hv.org, its post on the rocketryforum and Krazed III (the rocket it will fly in).

After the unfortunate death of the GPS tracker rev 2, I decided that the next revision would have a microprocessor on board so that I could fire charges remotely (chicken switch). That then lead to having a few extra sensors, and then I needed some memory to store all of the extra data in, and a new power supply to keep everything running off a single LiPo cell, and I ended up with the following list of requirements:

I then started searching for suitable sensors, and came up with this list:

After those parts came in I spent some time with a breadboard (and some creative ways of hooking all of the surface mount or even leadless parts into my breadboard...) an got some proof of concept code working for them all.
tracker tracker

And then drew up a schematic and did a board layout: (note, there are some errors in these, for reference only)
schematic layout

I then tried to etch my on PCB for the tracker, but ran into all sorts of problems. Of course it was not until after I reworked all of the imperfections in the board that I realised I mirrored the wrong side of the board and it was completely useless. Lesson learned, when there are tons of vias, and really small traces, don't try to etch your own board out of 4oz copper clad, just use batchPCB.com
But if you must see it, there was a few days worth of work I really wish I could have skipped...
tracker tracker

and populated the board:
tracker tracker
tracker tracker
tracker tracker

I flew it in Krazed III on 10/13/07, on a I287 2 times, and on a Hypertek J317 once on 4/6/08. Unfortunately, the code to use the flash memory wasn't working, so the only data I have is the 1hz location/altitude/acceleration data. See Krazed III's page for the data.

I am currently working on the code, and have had a number of sucessful flights on the revision 0 code
If you would like the alpha code, email me.

Everything on this site (pictures, schematics, code, etc) is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License, which essentially states that you can do whatever you want with it, so long as you

If you need a different license, contact me.

questions? comments? Want to help? email me contact@krazerlasers.com

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