We found this circuit in the October 1996 Electronics Now magazine. The circuit uses LDRs as sensors and drives relays. The relays must have voltages according to the power supply.
This is a high efficiency version with the MC723 which is the Motorola version for this well-known...
This circuit was found in the March 1997 Electronics Now magazine. It uses a common analog...
This circuit is from an 80's documentation. It makes use of two SCRs with current capacity...