Moving Coil Circuit

Question

My wife and I are planning a Robot themed room for our 1st child which is due in May. My goal for his, yep its a boy, room is to make a wider variety of sensors that will hang on the wall that will each display a different input.

For my first sensor I want to build a simple sound measuring device that will use a moving coil meter and an artsy fartsy backdrop. The problem I'm having is trying to hook up the electret to the moving coil and was wondering if someone out there had a schematic.

Answer 1

I believe what you want is called an analogue VU meter, and the mic won't generate enough power to move the needle.

So what you need is a microphone preamp. I found this circuit on the internet which should do the job: