My ATO is driven by a 9v battery and it uses them up fast. Does anyone know what type of transformer would work to replace this?

Thanks

Mine used 9v batteries as well. I just wired in a spare 9v 500ma brick I had lying around from an old cellphone charger. Look around your house, I'm sure you'll find a 9v brick you don't "need". :)

If you can't find one, I've got a spare you can have.

I know pinpoint has one they sell for $8.99. They use it to replace the 9volt battery on their monitors.
http://www.marinedepot.com/ps_ViewItem~idProduct~AM1421.html

thanks I wasn't sure about the current but it is small enough that it doesn't look like it matters.