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.
September 2016 - It can be purchased from Mouser Electronics the new antenna tuning circuit from...
This circuit uses a selector switch to select resistors for timings given in seconds. Capacitor C1 can be...
This circuit trips when the input voltage exceeds 13.8 V, which is an important value in the case...