The PC Engine didn't have an RF out jack, just molded plastic of the shell in its place. So the PCE itself couldn't be played on its own, even if you had a compatible power supply.
weird. IIRC, can't you supply it power through the expansion bus?
I think tiger was saying that he has a model that was boxed together with no seperate power jack, so it would have to be plugged into the IFU that it came with to function.
I recapped a PCE like this at one point for someone, and tested it in an IFU.
Yes, guyjin you can tap 5v power from a few places on the expansion bus, and also from Pin 38 of the Hu-Card slot.