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Table of Contents
Mission: Two - Tethered Ballon Drop Tests
Aims
Components
- Payload from Mission One
- Gumstix 400xm
- Audiostix II
- 3 degree accelerometer
- Rate Gyro
- Jupiter Rockwell GPS
- Servo Snooper
- Aerocomm 868Mhz Radio
- Cutdown device
Construction
GPS
GPS is a cheap Jupiter Rockwell GPS unit that was bought off ebay for £10, its relatively large for a gps unit but out puts at TTL so can easily be wired up to the gumstix's TTL serial ports. Information about the pinouts etc can be found here. As a warning the rockwell jupiter has annoyingly spaced pins which require a special socket so instead of that hassle using a soldering iron i removed the pins and directly soldered wires to the holes that the pins sat in originally . Also this hack reduces the height of the gps making it easier to intergrate. The GPS requires an antenna which attaches with a mcx connector - I also got one of these off ebay (you can also get them from maplins) - the cable was far to long so i shortened it by cutting a section out and resoldering the two ends being careful to keep the different bits of the coax cable seperate. I used an active antenna so added a power line from the gumstix. One thing i've noticed is when the gps is powered on and the gumstix is off the nmea pulses seem sufficient to cause the gumstix light to flash in time. Doesn't seem to effect the gumstix but will require some more investigation (perhaps something to do with the common ground).