Initial Ideas

So, one of the main problems with real-time telemetry is that it deteriorates over long distances, and the transmitting frequency is affected quite a bit with temperature changes. I thought about using plain old serial comms over a 900MHz link (similar to Natrium's launch) but that didn't work very well, and also, the UK is stringent on it's transmission rules. It turns out there are only a few frequencies 'allowed'; a tiny range in 434 (@ 10mW) and 869 MHz (@500mW). This rules out the 900 option completely, and many other higher power transmitters which may be able to 'blast' the signal hundreds of miles without issue. Ideas were needed...

The UKHAS site has plenty of hints, tips and pointers. The standard used here is RTTY, and suits this application of low power, long range communications.

I also thought I could add a 2.4GHz micro cam to the payload (I know the range won't be amazing - but could be good?) and then I thought I could add the same Gumstix micro computer as the Halo project; having a webcam take a series of pictures. The payload and complexity was increasing....
anyway, bought the Gumstix:

The Beginning

Well, where to start. Back in 2008, I saw this one day, and I'm sure you'll agree, I thought it was quite cool:
http://www.natrium42.com/halo/flight2/

I then had a think and reckoned - I could do that, maybe even improve upon it, and see what other people are doing out there on the interwebs.

It soon became apparent that the UK had a little group of dedicated High Altitude Ballooners... and every one of this intrepid band had differing experiences, and indeed, objectives, for each 'launch'. Mainly, though, for pictures like this:

from the header of the UK High Altitude Society (UKHAS) website; which is the place to start. Many folk involved aren't necessarily from the UK, with avid participants from Australia, South Africa, Holland and America amongst others.

Further hunting around showed up a few guys who had successfully devised, planned and launched payloads with on-board cameras and radio telemetry.

The three main influences upon me were the following:

• Robert Harrison; whose Icarus project gained some publicity. His ideas and code seem to be amongst the basis for many high altitude balloons.
• James Coxon's PegasusHAB - tells the story of many projects and the evolution of student playing and tinkering to full on 'pushing the boundaries' of what can be done at high altitude.
• Project Horus down under in Australia has some nice ideas and some polished code which is proven and some of which I have 'borrowed' - cheers Juxta/Darkside ;)

There are many many other contributors to the active mailing list and highaltitude IRC channels to name; hobbyists, students, teachers and engineers. Each bringing ideas to the table, and all very generous with their findings (and more importantly - working ideas, assistance & code!).

My original thoughts were simple; a camera and realtime telemetry....
but projects evolve.