This circuit came out in a 60s RCA documentation. The circuit uses common lamps and LDRs but can be implemented with LEDs.
This charger for a maximum current of 15 A was obtained from an American 80's schematics. The triac must...
This circuit is from the 1971 Motorola SCR Power Control Fundamentals. The circuit can be made...
This circuit, published in 1988, uses several types of sensors and relays to activate warning...