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From: MBF%cmu-cs-c@sri-unix.UUCP
Newsgroups: net.micro
Subject: Atari video bars...
Message-ID: <1949@sri-arpa.UUCP>
Date: Wed, 8-Jun-83 18:56:00 EDT
Article-I.D.: sri-arpa.1949
Posted: Wed Jun  8 18:56:00 1983
Date-Received: Tue, 14-Jun-83 05:30:38 EDT
Lines: 12

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
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