This is an adjustable light sensor. Use Digikey TSL254-R-LF-ND (AMS TSL254R photodetector) for the voltage supply attached to the negative input of the op-amp (0.01V = dark, 1V = daylight, 3V = bright light). Use Digikey LM4250CN/NOPB-ND (TI LM4250) for the op-amp. Use Digikey PDB241-E420K-504A2-ND (PDB24 500k logarithmic) for the potentiometer. Use Digikey 255-1092-ND (HY1-5V) for the relay. Use Digikey 1N5817-TPCT-ND (1N5817) for the output diode of the op-amp. Everything else is generic.
