The tiny solar cell chip presented a couple of days ago has been doing some indoor sun-bathing:
I’ve left it alone for some 3 days, just to give it a chance to charge up the 0.47 F supercap as far as possible. The voltage after all that time (partly sunny on most days) is now only just over 2.78 V, so this isn’t really going to work indoor, I’m afraid. Nor outside during the winter, probably – it’s just too weak.
The other solar cell I tried is also a very small one, rated at about 5V but only 1 or 2 mA, IIRC:
It’s currently in the shadow, but during these same 3 days it has had its share of sunlight (still indoor, and again behind double-glazing). Much better: about 4.75V on the second day, and unchanged since then.
This might actually do the trick. I’ll wait for another experiment to finish and will then hook up the JeeNode running my radioBlip sketch to see how it goes.