This circuit allows the use of an electret microphone with a 1.5 V source. We found it in the Encyclopedia of Electronic Circuits volume 5 from 1995.
We found this trebble booster circuit in a 1990 documentation. The components are current, and the...
This circuit for the experimenter of the 60s allowed testing the most common transistors in the...
In this application we use an additional input circuit to enable the logic command with keys,...