This circuit, suggested by an Electronics World of 1969, keeps a blinking LED for a while when a power outage occurs. Time depends on capacitor C1.
MXT1665T-A Family from Microchip Brings the User Experience of Multi-Touch HMI into the VehicleCHANDLER,...
This circuit reverses the signal if both positive and negative. We found it in an American...
The displayed relay operates with an audio signal applied to the input. The transistors can be...