So I've been the proud owner of a Twin Famicom for a few months and it worked like a charm, until this evening when I tried loading it up and I knew instantly from the sound that the belt had broke.
I went through and was able to replace the belt just fine, but now I get error 22 constantly. I've tried every disk I have and nothing. I'm pretty sure it's the spindle. I've been tweaking it over and over but still nothing. Is there some kind of trick to getting the spindle calibrated properly?
Also, if it isn't the spindle, what else could it be?
It's probably either the height of the spindle head or the read head is dirty. Could be something else, though.
there's a lot of tricks to get it calibrated correctly, and about other things that could be the problem... if you search the board I think you will find some suggestions. :D
http://www.famicomdisksystem.com/tutorials/fds-repair-mod/belt-replacement-adjustment/
Later half of the tutorial should get you back up and running. Got me working like a charm.