This circuit is from the time when photos were revealed in darkrooms. We found it in a 1968 Electronics World. The circuit can be used for other purposes.
Using two common operationals, such as 741, this circuit serves as a medium control in an...
We found this circuit in a 1979 documentation, but it can be changed to use more modern...
This circuit was found in the October 1983 Radio Electronics issue. It is applicable to old analog...