Voltage "guage" type of circuit Hi all, I have a windmill gearbox, connected to a generator. At the lowest speed, the generator outputs ~ 100 mV. At the highest practical speed, it generates ~2.8 V. I'm trying to make a graphical display that is proportional to the output voltage of the generator. In simpler terms, I have a DC power supply that sweeps from .1 to 2.8 V. I would like the LEDs to turn on at .3 V intervals. I've racked my brain, my electronics books, etc and am stuck and have turned for help. I cannot have any external power sources (to power any type of IC). The idea I'm toying with now is Diodes. This seems like a very simple problem, but I am stuck. I don't need a schematic, just a shove in the right direction. Thanks so much.