Its exactly what it looks like! probably the EASIEST thing you could possibly do. to plug into any CV input! for a bit of expression. and actually quite accurate expression too! I was able to play it like a theremin when its into pitch.
Above you can see a panel with 5 different Solar panels. they are literally glues onto the front, then a hole is behind them with the wire poking out, then you solder the wire directly to the jack socket! - to ground and + to the tip of the jack!
It doesnt really matter which solar panel! all inexpensive ones suck! so you wont blow up anything, the ones i use i think are rated at 6v. and were £3 each off EBAY.
In the picture at the top youll notice there at lights underneath, thats because its dark in my workshop! so a bit of light never hurt. When i take these out to be used out and about its good to get people to get out there phones and mess with them! its a great way to make synths interactive without having people pulling knobs off and pulling jacks out like they are carrots in a field! barbaric.
CHECK THIS VIDEO I MADE.