This LED bar graph circuit was found in the October 1980 issue of Radio Electronics magazine. The circuit shows how to change the LED drive values.
In this circuit of a 1991 publication, we can use the 2N2646 unijunction transistor and the sensor...
We found this circuit in a Mullard manual from 1960. The transistor is a phototransistor of the...
This circuit triggers a load that depends on the characteristics of the transistor when we touch...