MBF%cmu-cs-c@sri-unix.UUCP (06/09/83)
One trick to fix this problem, discovered very early in the machine's existance, is to put .1 uF disk ceramics (or MLC's, or whatever) across the big ripple-filtering electrolytics and voltage regulator outputs. Atari violated common design practice for the monolithic voltage regulators by not decoupling high frequencies to ground with such capacitors, the net result being that a sizeable portion of 400's and 800's are plagued with video problems resulting from oscillating voltage regulators. hope this cures your problems, Mark Dzmura via mbf@cmu-20c -------