Found in the July 1994 Electronics Now magazine, this circuit drives a relay up to 12 V depending on the power supply. The transistor can be general purpose.
This 5.1 MHz oscillator was found in a 1980s American documentation. The used operational...
This configuration has already been used several times in many of our projects and can be found in...
This simple circuit makes use of neon lamps to indicate the voltage of a power grid. The lamps are...