Firefly High Altitude Lifting Platform
By James Coxon (jacoxon@googlemail.com)
Modular lightweight payload with simple GM862-GPS backup system (sms and morse radio) - allows for experimental payloads with the fallback tracker system. Once the basic system is complete and tested potential experiments include 2 way radio communications, video streaming, sunrise launches, etc.
Launches
FHALP-1 - 24/11/07 - landed in the sea - oops 17/22/07 4/11/07 - Test backup system, GM862-GPS, SMS and Radio comms (morse), single camera.
Modules
- 2 Way Radio Module
- Sensor Module
- Propulsion Module
GM862 Uploader
I wrote this front end to make it easier to access and upload scripts of the GM862-GPS module. Its written in RubyCocoa.
Zip file of Xcode and PPC Binary here
Radio
The radio module on Firefly transmits an adapted version of Morse Code (as Morse Code isn't optimised for just numbers) which was originally suggested by mc-.
| Number/Char | Code |
|---|---|
| 0 | - - |
| 1 | . |
| 2 | .. |
| 3 | … |
| 4 | …. |
| 5 | - |
| 6 | -. |
| 7 | -.. |
| 8 | -… |
| 9 | -…. |
| - | .-. |
Field Strength Monitor
For the backup radio on Firefly I got a N5 module and to test it I made a simple field strength monitor (circuit diagram from RF Circuits}. I didn't have a 3M3 resistor so used 3 x 1M and a diode I found in my box of bits. The multimeter hovers around 0 when the radio is off and goes up to about 4 when its on.
