Obtained in a 1968 Electronics World, this circuit uses transistors from the time and the sensor is a common LDR. The component values are for scales from 0.01 to 100 foot-candle.
We found this circuit in an American 80's documentation. The circuit can be adapted to function as a...
This 80's circuit, suggested in Texas Insrtruments documentation, uses a Hall effect sensor. The...
This interesting benchtop circuit was found in the May 1977 issue of Radio Electronics magazine. The...