So last week I nervously turned up with my laptop and some kit. I had created a Power Point presentation to hopefully explain the whole concept. It was an introduction to HAB, the types of payload and balloons how they work, how operators track the flights and the UKHAS and its HabHub system.
To demonstrate the use of the DL-FLDIGI decoding software I had a few SDR recordings which I could play back. I also wanted to show how you could use a conventional receiver so I created a 'demo payload' in a plastic lunch box.
It consisted of a simple PMR446 radio in VOX mode, connected to a MP3 player which was playing back a recording of a typical RTTY HAB payload. Steve Smith G0TDJ of ProjectHab was good enough to supply me a 4 minute recording of his VAYU-1 payload made when he was testing it.
I then had a scanner which received the transmission, so being clearly audible I was able to plug a lead into the headphone socket and the microphone input on the laptop to show the decoding.
I also demonstated some SDR recordings being decoded which illustrated the QRM, signal fading and drifting and some of the modes in use (RTTY/DominoEx). I also had videos showing the http://spacetracker.us/tracker in action (also posted on here).
Despite being apprehensive I actually quite enjoyed giving the talk and hopefully those that attended were entertained and found it informative.
Since then I have took the plunge and ordered a couple of transmitter modules including a Radiometrix NTX-2, an Arduino UNO development board and a uBlox GPS module so can start developing my own payload. So hopefully if I am asked by anyone else to give a talk I can show a live demo!