Convert DC Power Jack to 9V Battery

I have a PCB which has a spot for a DC power jack, with three pins, but i'd like to use a 9V battery instead. Can anyone help me out on which pins are positive and negative?

No, because you didn't post with any pictures that might be able to tell us what we need to know.

By the way, a 9 volt battery is almost never a good idea, they can't produce anything more than a high (if you count 9 as high) voltage source, or very very very low currents for a long period of time.

For some reason my images won't upload, but the 2.5 mm dc jack is center positive. I see that the center connection corresponds with the pin on the back of the jack, so I know where positive lead goes. Does that mean the other two pins should be negative? And would you recommend a different power source than 9V? The chip has an operating voltage of 2.4 to 5.5V. I'm using the 120 Second Voice Recorder Module found here: **broken link removed**