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 simple alarm circuit was found in a 1998 documentation. When the sensors are activated, the...
This circuit was found in an old American documentation. The integrated circuit used is uncommon...
Found in a 90s Electronic Design, this suggestion to have a higher voltage in a fixed regulator...