By combining 49 of them he’s put together a soda bicarb diode steering circuit for a 7-segment display capable of showing the digits 0 to 9. He takes the idea for his diode from electrolytic ...

Besides, if you want to use them, you need to work with high voltage supplies and worry about not getting zapped while trying to debug a circuit ... a regular 7 segment LED display.

seven-segment display (Image courtesy of LXD, Inc.) In their natural state, liquid crystals line up with the orientation "rubbed" into the front and rear glass panels. The rubbings are microscopic ...