I just got this today and it's vexing me to the point of insanity.
I've been probing for about 3 hours and have found a few glitches and that's pretty much it. I've not been able to find a pitch bend or loop or anything remotely remarkable.
I had a look for schematics via the gift of google and found the coleco circuit but not the matchbox/tiger one, which happens to be the one i have. The main thing that I noticed on the coleco was the lack of a crystal/xtal. the matchbox version does have one, and i'm fairly sure that it's the reason I can't find a pitch bend.
Will replacing the crystal with any other component be of any use, or will it just break this infernal machine?