can i get a new circuitboard for my treadmill?

You need to contact somewhere like this...

http://www.treadmilltalk.com/treadmill-parts.html

in your country - but first you need to determine the Make Model of the equipment...

Replacement PCBs for most consumer goods are prohibitively expensive (about ten time what they cost to manufacture) and you might consider asking a friend with electronics skills to try a diagnosis & repair for the price of a few drinks perhaps...

Good luck...

Peccavi
September 2009