>will this work for just a poly800?From what I can tell, most mkI's didn't have sys-ex, but it is possible
to replace one of the chips to add the functionality. I guess the main
problem is tracking the chips down (the ROM chip, I think). Think you
can replace the mkI one with a mkII, and give you the sys-ex functionality.
But with most mkI's, you can't, it's audio-source only.
Lee
http://www.baudalign.com/poly800.html