This circuit was found in documentation from the 1980s. The circuit uses several components of the time, which are uncommon today. We must not supply it with a transformerless power supply.
We found this CMOS circuit in a 1978 publication. It allows you to use a standard calculator...
In the figure we have an oscillator for microcontrollers capable of operating in the frequencies of 10,...
This fast Schmitt trigger operates at frequencies from 10 Hz to 100 Hz, with very short rise time....