I've also been tinkering with homebrew flight instruments for recreational flying. These are open source projects - full source code and schematics are available to download.
An audio-only variometer that evolved from one of these designs is now available for purchase at Flytepark.
The Flytepark Nanovario was tested and approved by Chrigel "the Eagle" Maurer, during the 2013 Red Bull X-Alps competition. This year's edition was a gruelling 1050km hike-and-fly paragliding race from Austria to Monaco through the Alps, where every gram of weight had to count. And Chrigel set a course record, finishing in 7 days!
And talking of other things, a personal story in the Diary link. This was not something I wanted to publicize like this, unfortunately ...
Har-in-air Bangalore, India
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