This circuit was found in a Hands On Electronics from the 90s. It is intended to supply old tape players to batteries with a voltage of 7.5 V from the 12 V of a car battery or source.
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....