We found this circuit in an American documentation from the 80s. The integrated circuits are operational amplifiers of the time. We can test modern comparators like the LM339.
This circuit was found in an Electronics Now of 1988. The circuit is still current, and the power...
With this name, we found this electronic stethoscope with a coal microphone in a 1957 Raytheon...
This transistor amplifier with complementary symmetry configuration can provide approximately 1 W...