Hi everybody!
I'm new here, my name is Koen and I study at the University of Twente in the Netherlands.

For electronics, we have to build a circuit. The circuit has to have two microphones and two LEDS. The microphones and LEDS are placed in the opposite of each other (one left, one right). The goal of the circuit is that the LEDS are always shining at +-50% brightness, but when somebody talks in one of the two microphones (Left or right), his LED becomes brighter. The other LED will still be shining at a 50% brightness. If the other person talks harder, his LED has to become brighter, and the other LED has to shine at 50% again.

So there has to be a comparison between the two microphones, so that the side (left or right) with the highest sound input will be the side where the LED will shine the brightest. The other side will be shining at 50% brightness. If the person stops talking, the LED will return to it's 50% standard brightness. Another requirement is that the circuit runs on 5V or 3.3V, and we can not use a Arduino.

I have these microphone boards: http://www.icstation.com/analog-sound-sensor-microphone-controller-p-1910.html

It would be great if somebody can help me! I have done some research, but never found out how this could actually take place. I will be very thankful.

 

Start by characterizing the module; range, sensitivity, output, etc. You have to work with what it produces....

(ps. I'm sure that some of that is in the zip file, but I don't open zip files...)

 

On the face of it, the product http://www.icstation.com/analog-sound-sensor-microphone-controller-p-1910.html will not serve the the full purpose. Yes, it will act as a nice mic amplifier, but as per your requirement, the output of the 2 mics have to be compared and the louder one's LED selected.

So there has to be a comparison between the two microphones, so that the side (left or right) with the highest sound input will be the side where the LED will shine the brightest.

Maybe it will be possible to do this with the available setup in the "controller module", but it will require the tracing of the module schematic.

 

I changed my plans. According to the info that the mic only gives a 0 or a 1, it is better to just let the LED shine when one of the mic's is giving value 1. I mean that the first mic that gives value 1 will make the LED shine brighter. If the other microphone is triggered at the same time, nothing will happen. If it's quiet again, and the other mic gets triggered, then the other LED will shine.
That seems possible with those microphones which only give a 0 or a 1 as value.

 

those microphones ... only give a 0 or a 1 as value.

The pic of the board shows an 'AO' pin. Isn't that an analogue output?

 

I changed my plans. According to the info that the mic only gives a 0 or a 1, it is better to just let the LED shine when one of the mic's is giving value 1. I mean that the first mic that gives value 1 will make the LED shine brighter. If the other microphone is triggered at the same time, nothing will happen. If it's quiet again, and the other mic gets triggered, then the other LED will shine.
That seems possible with those microphones which only give a 0 or a 1 as value.

I think a SR FF should do the job of selecting the "active" mic. The S and R will be the "DO" from the mic modules. This works if Only 1 mic is active at a time.

If both mics can be active and you need to control the LED's on a "First Talk First LED" basis, you can manage by a couple of "re-triggerable" monos and NAND gates.

 

Hi!
I managed to make it work. Here is the scheme.
Thanks!


Circuit.