This circuit uses an 18 MHz crystal to generate 36 MHz signals. We found it in an 80's documentation. The circuit has an input for frequency modulation.
This contact or reed switch actuation was found in a 1964 Electronic Design. The circuit can be...
This is the previous version, but with a simplification given by the use of the 7404 and 7408...
In the figure we present a circuit of a microphone signal conditioner using the SSM2167 integrated...