Hey there,
Does anyone know if the DC port on the back of the Mindstorms RCX is tip positive or tip negative? I have tried to determine it, but you can’t tell just by looking inside, multimeter tests etc. I already have a 9V adapter with various connectors, it would be great if I could use it for this project and save some cash (college student budget). Just wanting to make sure before I fry one of these. Last semester I fried an instrumentation amp or two by reversing the polarity; an RCX is quite a bit pricier than those.
Thanks!