Arduino Uno + Velleman Microphone Sensor

Other Hardware Audio
1

I am using:
Arduino uno
Velleman Micorphone Sensor VMA309.

The Velleman have connections, and diagram is:
Arduino --- VMA309
A0 --- A0
GND --- G
+5 --- V + (5v)
D0 --- D0
(Which I have connected)

I can spinn the pot and recive values (on serialmonitor) betwen 0 and way above 1000 (with analogRead) Very simple code snap:

void setup() {
  Serial.begin(9600);
}
void loop() {
  Serial.println(analogRead(A0));
}

I can also spinn the pot and change the threshold for the sensor onboard led to turn on, and the digitalRead works for detecting that threshold as well:

void setup() {
  Serial.begin(9600);
}
void loop() {
  Serial.println(digitalRead(D0));
}

My problem is that it barely detecting any sound. I set the pot about 0,1degree from when it lights up, and still I have to scream loudly (or hit something very hard on the table) in order to trigger it.

the analogRead jumps between 10-20 units out of 1000 when I smash something really hard att my table, smashing my hands is barely enough (and the table almost breaks)

Any idea? I've tried with different delays in the code as well. I am thinking if I need some sort of sample converting function, but nobody else have done that.

2

That is likely the source of your trouble. NO delay is necessary.

Your test show the device is operating properly. What is the quiescent A/D value your are getting? Your sound should be anything greater than that value.

3

The module has no analog amplification. Only a digital threshold detector. So the microphone can't be very sensitive. But if the digital output can't be set for reasonable sensitivity, then the mic capsule might be bad.

Realize, it's an extremely simple circuit:
https://www.velleman.eu/downloads/29/infosheets/vma309_scheme.pdf

4

I had to do a quick search on quiescent A/D value. Did I get it correct if I measured:
5v+ to GND = 5.05vdc
A0 to GND = 2.43vdc
(did this earlier, but not the D0)

5

I've worked with tree small identical mics and now the bigger model, with the same result. I've searched and tried for years. All of them seems broken. What am I missing?
Thx for the drawing, but Im still struggling

6

A microphone preamplifier. Or, your unknown sketch is not reading the values properly (more likely actually). Or both.

7

The quiescent A/D value will be an integer that your read from the A/D pin. You have not told us the value you read. Please do.

8

It really depens on how I have the pot set. I've attached the plotter diagram.
but with music and noice it doesn't move, but it does move with a really loud noice.

Analogread
Analogread1910×775 115 KB

9

The reality is your sensor is working just fine. Just not what you want.

10

With no horizontal time scale.

11

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