This oscillator that generates signals below the audible range (sub audio or infrasound) was found in a 1965 documentation. Transistors are for general use.
Found in an American publication from 1968, this circuit aims to keep the torque of a DC motor...
This shield can be used both to interface microcontroller circuits or TTTL. The resistor in series...
Found in Popular Electronics this circuit uses current components to control a pump in order to...