We had found this circuit in a January 1961 Radio Electronics Magazine. Using it is possible to take measures from the gain of transistor with a common a multimeter.
This circuit was found in an American documentation from the 90's. The circuit can use almost any...
This circuit triggers a relay when light strikes a sensor. The sensitivity is adjusted in the...
We found this circuit on the internet, but it has some problems. It will be convenient to limit the...