[Coco] Broken CC3

[Bruce W. Calkins]

> Well, I'm stumped.
> I found the power supply was clean after all, I think.
> AC noise on the 5V line is < 20mv. However, I'm seeing that noise on the 
> ground also. So I suppose this is just noise on the power line to the 
> scope.
Ground Loop?

> Is it possible the ROM in the coco could have failed?
That is a long shot.  The original is a masked ROM.  Basically, you would 
have to kill it outright.

Bruce W.