AndrewBurns
Jul 02, 2009, 07:33 AM
Have a look at this thread on a rocket forum I read:
http://ausrocketry.com/forum/viewtopic.php?t=1590
It's a build log of a simple open GPS telemetry unit, designed for rockets but no reason it wouldn't work in planes too (primarily designed so you can find your rockets again if they land farther than visual range away, could serve that purpose for planes too or just for altitude and other readings during flight). Basically it's a super-simple PIC based board, 1xPIC 16 series, 2 caps, a voltage regulator and a resonator, connected to a GPS unit and an off-the-shelf CB radio. The GPS sends the location data to the PIC via serial, the PIC encodes it as APRS packet data and then the CB radio transmits it to a ground station (another CB hooked up to the sound card of a laptop) which decodes the signal and displays/saves the location.
Of course the audio-out from the PIC board could be fed into any kind of radio transmitter if the CB handheld is too large and you don't need so much range. I just completed my unit and while too large for my DLG's I could easily (and probably will) fit it into my 2m electro-glider.
The guy doing the building in that thread isn't going to be making any more but he's uploaded the circuit diagram, PCB design and firmware plus pretty much all the info you need to make it yourself.
http://ausrocketry.com/forum/viewtopic.php?t=1590
It's a build log of a simple open GPS telemetry unit, designed for rockets but no reason it wouldn't work in planes too (primarily designed so you can find your rockets again if they land farther than visual range away, could serve that purpose for planes too or just for altitude and other readings during flight). Basically it's a super-simple PIC based board, 1xPIC 16 series, 2 caps, a voltage regulator and a resonator, connected to a GPS unit and an off-the-shelf CB radio. The GPS sends the location data to the PIC via serial, the PIC encodes it as APRS packet data and then the CB radio transmits it to a ground station (another CB hooked up to the sound card of a laptop) which decodes the signal and displays/saves the location.
Of course the audio-out from the PIC board could be fed into any kind of radio transmitter if the CB handheld is too large and you don't need so much range. I just completed my unit and while too large for my DLG's I could easily (and probably will) fit it into my 2m electro-glider.
The guy doing the building in that thread isn't going to be making any more but he's uploaded the circuit diagram, PCB design and firmware plus pretty much all the info you need to make it yourself.