I'm following this Instructable about the setup of the audio input for the Arduino Uno. However, despite having followed the schematic and the images very carefully, I still can't get the circuit to work, as the serial monitor keeps printing a constant value around 510.
The only change that I made from the Instructable, in fact, is that I'm not using a jack cable, but directly an electret microphone. I know, however, that this microphone requires power in order to function: therefore I hooked it up as explained here, with the difference that instead of the 5V supply provided by the Arduino I used the 3.3V (as the former was already needed by the circuit) and also, instead of routing the microphone output directly to pin A0, I used it as the input of the op-amp, as requested by the Instructable.
Unfortunately, neither this method, nor wiring the microphone up without even caring about the power work, but I simply can't figure out why, having had only little experience with electronics.
I would appreciate if someone provided me with some useful hints on how to get the microphone to work. If you would like more information, just ask.