SimpleTech Polarity

I heard Western Digital bought out simpletech. and Friday night I got an email saying the correct voltage and minimum amperage needed to run a simpletech FireWire 800 drive that’s one terabyte.

However the polarity wasn’t mentioned and I don’t know whether it’s tip positive or negative.

I heard you should not guess on polarities as well as voltages.

So is it tip positive or tip negative?

All WD Power Supplies … the Tip/Polarity is +positive