Found in a 1967 Electronics World, this oscillator changes its tone when objects move in their environment. The output is made on a low impedance phone.
This circuit uses NOR ports to generate signals up to 10 MHz, depending on the crystal. The supply...
The original transistor for this circuit from a 1973 publication is germanium, but a silicon...
With this name, the English publication where we found this circuit indicated a sensitive touch...