Shockwav3 Posted May 26, 2017 Share Posted May 26, 2017 (edited) Hello there, I'm currently servicing an Atari Video Music that was busted, so far I'm making quite fast progess (busted opamp replaced, modded for 230V and composite) and got it back to basic operation. There's one problem that remains and I'm having a bit of trouble to pinpoint it ... thing is whenever I select the horizontal divider of 5 (9th button from the left ... basically making 5 shapes appear in width, problem persists regardless of the vertical setting) the shapes get morphed instead of being perfectly symmetrical (making them look like 'arrowheads' instead of diamonds). A photo of the output is here: http://i.imgur.com/SFNDuqF.jpgIf my judgement is right the falling edges get smeared, while the rising ones are fine. Other settings work as expected. Any idea what specific part might cause this or is this likely a problem with the C1010280 custom chip? I've checked the voltages and test points pointed out in the schematic and those are fine. So are the voltages forwarded by the 'horizontal'-switches. Sadly I don't have a second machine available to confirm/decline a problem with the custom chip, but a good multimeter + a decent scope are available. Resources that might be helpful: Patent: http://www.google.com/patents/US4081829 Original schematic (bad quality scan): http://i.imgur.com/7pfBnlP.jpg redrawn (unconfirmed) schematic: atariage.com/forums/index.php?app=core&module=attach§ion=attach&attach_id=413189 Edited May 26, 2017 by Shockwav3 Quote Link to comment Share on other sites More sharing options...
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