This is the receiver from the previous alarm system. The circuit is from Radio Electronics, April 1989, and has an LDR as the sensor. Optical devices should be used to improve performance.
Up to 4 A can be sourced by this Power supply. It can be used to power automotive appliances and...
Found in a Popular Electronics from the 80's, this bridge allows the measurement of resistances in 5...
This circuit was obtained in a Hobbyst Handbook from 1990. The circuit can be easily assembled...