I’m trying to build a vibration detector by using an electet mic.
The circuit as well as the microphone is set within a wooden box. When someone hits the box, an alarm-sound should play.
So when the Voltage provided by the circuit exceeds a certain value in volts a variable for further dealing should be set.
The alarm sound with speaker and such is already done. The only thing missing is the mic. circuit.
My biggest fear is, that i destroy the Arduino Uno, since this is my first try creating a circuit with an electret mic. & an Op-amp.
So my Problem is the correct dimensions of the elements which are used.
unfortunately i don’t own an oscilloscope for proper testing
The circuit so far:
EM-5SB: The electret Mic.
NE5534AP: OP-AMP, inverting mode
R1, R2: Gain Modulation
Diode: rectification of the signal
R3: limits the current going into the Arduino Uno
So can anybody tell me:
- if the circuit is correct
- how the resistors (in ohm) and the diode need to be like, that i definitely DO NOT HARM the uno