This circuit triggers by choosing the higher of two voltages. The circuit is from a 1964 Electronic Design. The transistors are of the time and can be replaced by current equivalents.
The voltage regulator circuit described is highly accurate and uses discrete components...
WWV is the standard frequency station of the United States government. This station broadcasts a...
Based on a 555, this 80's American documentation circuit detects the voltage of a battery and can then...