This circuit is from a 1965 Electronic Design. The transistors may be general purpose and the power supply must be symmetrical.
The circuit is from 80s Siliconix documentation. The integrated circuit is from the company and is not...
This circuit that uses two LDRs as sensors was found in Radio Electronics magazine from November 1961....
The voltage comparator used in this application is the NCX2220 from NXP. What this circuit does is...