So I build this circuit (scroll to bottom of page). I made the same circuit as shown, but I used an LM358 and 5V arduino supplies. It works (yay!) but there is an annoying overlay of a high-pitched tone. So if I speak into the mic, it is my voice + annoying tone. All my cap + resistor values are co…

Amplifier

system March 6, 2011, 10:07pm 10

*now

Sorry.