Path: utzoo!attcan!uunet!cs.utexas.edu!usc!elroy.jpl.nasa.gov!jato!whoffman
From: whoffman@jato.Jpl.Nasa.Gov (Walt Hoffman)
Newsgroups: comp.sys.atari.8bit
Subject: Re: Improved Video Output
Keywords: Video
Message-ID: <4079@jato.Jpl.Nasa.Gov>
Date: 15 Jun 90 21:50:25 GMT
References: <12598055735018@osu-20.ircc.ohio-state.edu>
Reply-To: whoffman@jato.Jpl.Nasa.Gov (Walt Hoffman)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 33

In article <12598055735018@osu-20.ircc.ohio-state.edu> AJONES@osu-20.ircc.ohio-state.edu (Shawn Jones) writes:
>
>  Severaal years ago I saw a reference in a computer magazine to a mino
>hardware modification which would improve the video output from (I think)
>the 400 and 800xl's.  I was not able to keep the magazine or copy the 
>article.  Do any of you know how to make such a modification on a 1200xl?
>
>AJones


I dug up my archives and found the following modifications to improve the 
video output on a 1200XL.

      Originally         Change to

R22      4.3K ohm           6.2K ohms

R188     910  ohm        1N914 diode with cathode towards
                                    the bridge rectifier

R163     100  ohm           150 ohm

R145      n/c               18K ohms

I don't have a 1200 XL myself but a member in our Atari Club at work did
the mod and was quite pleased.


-- 
Walt Hoffman -- Jet Propulsion Laboratory
whoffman@jato.jpl.nasa.gov or elroy!jato!whoffman@csvax.caltech.edu
  Galileo Orbiter Engineering Team  --  Real-Time Analyst
     "Jupiter...it's not just a goal, it's an adventure."