This circuit was found in a 90s Popular Electronics. It is possible to analyze the voltages of an automotive battery. The integrated voltage comparator circuit admits equivalent.
This circuit is from a 1976 Motorola CMOS manual. It can be implemented with modern Darlingtons like...
In the figure we have the way of modulating or controlling the frequency of a relaxation...
The purpose of this circuit is to monitor the operation of an alternator in cars with a 12 V...