Testing a new sound sensor.

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Hi! My name is kaizokuj and I bought an arduino starter kit about a month ago and since I've been playing around with it almost daily. Recently I bought my first part that was not from the kit! I bought a sound sensor but I can't seem to get it to work.. I've made a post before on reddit but didn't get much response, so I'll just quote my original post if that's alright!

So today I went and bought the first extra part since I got my kit about a month ago, A sound sensor, El & verktyg - Produkter | Kjell.com

On that site there is a link to some example code but sadly no schematic for the example they gave so I improvised: Imgur: The magic of the Internet

The code they gave is this: int DO=2; //Pin for Digital Output - DOint DA=A0; // Pin for Analog Output - - Pastebin.com

However when I run it and check the serial output it's showing an almost constant analog output of 26-30 and a digital output of 1 no matter how much noise I make, what did I do wrong?
EDIT: Found this international link: Recommendations For You - DealeXtreme

Thanks in advance for the help :slight_smile:

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No schematic and no hook-up diagram is sort-of a BIG PROBLEM! :wink:

You should only need 3 connections: Power, Ground, and Analog Out. I assume the + pin is power (+5V) and it looks like you've got it going to ground.

I see the LED is on so the board is getting power, but I have no idea if it's getting powered correctly. If you hook-up something like this wrong, there is always the possibility of destroying it.

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Here's a page with some reviews of what appears to be the same product: DX New Forum – Discuss Cheap Electronics and Find Smart Tech Here. From what the reviewers say, the output is unamplified, and the single integrated circuit on the board is a comparator rather than an amplifier. Conventional wisdom says you need amplification on the order of 100X with an electret, on a 5V system. In order to use it meaningfully, you will probably have to add an op amp. You can see how sparkfun did it, here - https://www.sparkfun.com/datasheets/BreakoutBoards/Amplified-Mic-v10.pdf.

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Yeah sadly no schematic was on the website that had the code..
A guy in the reddit thread said that one of the components on the sensor can and most likely does act as an amplifier.
Here is the original post:

http://www.reddit.com/r/arduino/comments/2414gw/testing_a_new_sound_sensor/

As for the LED, if I take down the threshold from it's original value (400 something) it lights up. So I think it should be working as it should, however the sensor doesn't even increase a little no matter how much noise I make.