This circuit of an old medical publication makes use of an integrated circuit of the time, uncommon in our times. The sensors are diodes.
This simple CMOS touch switch was obtained in a 1987 publication. All components are common and the...
This circuit is from a current regulator up to 1 A, ie a constant current source. The LM320...
Found in a Popular Electronics from the 90s, this circuit reaches 100 kHz and battery power is...