“A few years ago I built a Variometer with the help of Andrei’s Instructables.
It was working nice, but there were a few things I didn’t like.
I powered it with a 9V battery and this took a lot of space and endet in a bulky wooden case for the electronics. Often on the most promising day’s the battery got empty and I didn’t have a spare battery with me.
So I decidet to change this and designed my own Version of a Vario inspired by Andrei.
My main goal was to make it smaller and rechargeable.
Since I wanted to use an SSD1306 as display I also had to write the software from scratch.
Because I struggled with the altitude calculation logic (I am not a C programmer) I reused a few code segments from Andrei’s Sketch and his libraries.
The result was a decent 8x3x2cm vario with just the minimum functionality.”