This two-digit timer was found in the 1983 Special Projects issue of Radio Electronics magazine. The circuit uses components that can still be found today.
This second amplifier is based on the integrated LM108 and has a differential input. The resistor...
This circuit was found in a 1968 Motorola documentation. The circuit can be implemented with...
Nothing more useful on the bench than a variable voltage source. This is the source we found in...