Dave,

You are correct. I hadn't looked at the standard codes and as you probably figured out it is NEC1 Protocol Device=122 and that is Setup Code Audio_0176 or Audio_1176. I also noticed that there are discrete power commands under that device code as well and they are On=OBC=29 and Off=OBC=30. Those correspond to EFC=248 and EFC=246.

So you might try those setup codes to see if any commands work and also try this other set of discrete power codes by the "assigning advanced codes" method covered in the RS15-1994 manual at www.hifi-remote.com. This can be done without a JP1 cable, if you don't have one yet.

Let me know which works, I am surprised that here are apparently two sets of On /Off codes so maybe they are used in a different context. I have no direct experience with any Yamaha equipment.

-Jon