This circuit is based on the light comparison of two LDR sensors. We found it in a 90s Popular Electronics. The transistor must be according to the indicator or load being driven.
The operational amplifier used in this project no longer exists, but the circuit can be adapted to...
With S1 closed, when dark, the triac will supply the load with the power set in R4. The LDR is...
Toshiba LDO Regulators Toshiba has a wide variety of low voltage drop (LDO) linear regulators...