This circuit of a 1964 Electronic Design uses a photodiode from the time. Modern equivalent can be used. The standby current is 1.2 mA.
This simple circuit for a common 110 V power grid was found in a 1980s American documentation. The circuit uses...
What this circuit does is to stretch a pulse, increasing its duration. The integrated circuit is...
This simple circuit was found in a 2001 documentation. With each touch of CH1, a 4017 output...