We found this circuit in a 1965 Electronic Design. Transistors are still common but admit equivalents for some of them. The circuit drains a current of only 4 mA.
MCP19124/5 Contains Independent Voltage and Current Control Loops Plus a Full Suite of...
A flash of light on one sensor or the touch of your fingers on the other type of sensor will turn...
This 1-transistor timer was published in Radio Electronics magazine in December 1960. The circuit has...