This circuit of starting lights for auto-race was found in an English documentation from the 80's. The LEDs must be of different colors, for greater realism.
This circuit for link or alarm was found in the Encyclopedia of Electronic Circuits Volume 5 of...
This 9-pixel circuit has been implemented with 9 LDRs and can be coupled to a processing system for...
The purpose of the diode in this oscillator circuit is to limit the amplitude of the output...