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.
Of course, with a change in the cable length, the frequency can be changed as long as it is within...
This circuit is basically the same configuration as the previous one with a power stage with...
Using the ZN1034E which reaches 19 days interval, this is a simpler circuit which can be...