A-T-A-R-I Posted March 15, 2010 Share Posted March 15, 2010 (edited) I was playing Circus Atari tonight and notice now that there is shadowing on my blue screen. From the left to almost the middle of the screen, the coloring is a deeper blue and when I turn my paddles left to right, you can see the shading change as well as movement of the shading up and down. Anyone know a fix? I reflowed the whole board and changed the 3 chips to see if it would make a difference, but the problem is still there. Thanks Edited March 15, 2010 by A-T-A-R-I 1 Quote Link to comment Share on other sites More sharing options...
A.J. Franzman Posted March 15, 2010 Share Posted March 15, 2010 (edited) I was playing Circus Atari tonight and notice now that there is shadowing on my blue screen. From the left to almost the middle of the screen, the coloring is a deeper blue and when I turn my paddles left to right, you can see the shading change as well as movement of the shading up and down. Anyone know a fix? I reflowed the whole board and changed the 3 chips to see if it would make a difference, but the problem is still there. It may be a problem with your TV. Can you try another TV, or a different console? If neither, can you at least post a screen photo? Edited March 15, 2010 by A.J. Franzman 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 15, 2010 Author Share Posted March 15, 2010 (edited) Does it on all tvs in the house, but only using this console, so I am sure it is something with this console. Here are some pics, not that great. Really strange. When you turn the paddles, you can see movement within the darker area going up and down. Edited March 15, 2010 by A-T-A-R-I 1 Quote Link to comment Share on other sites More sharing options...
zylon Posted March 15, 2010 Share Posted March 15, 2010 Try changing the channel up one and then down again on the tv while a game is on. Could be interference or slightly off tuning. 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 15, 2010 Author Share Posted March 15, 2010 Tried that, still no change. I notice it seems to be only affecting the blue and green background screens. 1 Quote Link to comment Share on other sites More sharing options...
Tom_Explodes Posted March 15, 2010 Share Posted March 15, 2010 Have you ruled out the RF cable by trying a different one, if you have another one? I don't know if that's helpful, but worth a shot, I guess. 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 15, 2010 Author Share Posted March 15, 2010 Changed RF cable, no difference 1 Quote Link to comment Share on other sites More sharing options...
Osbo Posted March 15, 2010 Share Posted March 15, 2010 Bad RF box, use one of these: http://atariage.com/store/index.php?l=product_detail&p=42 or just do the A/V mod and get rid of the RF altogether. 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 15, 2010 Author Share Posted March 15, 2010 I forgot to mention this is a six switch model. Can't be the RF box. I tried two other switchboards (which have the rf boxes mounted on them) and no change. 1 Quote Link to comment Share on other sites More sharing options...
Osbo Posted March 15, 2010 Share Posted March 15, 2010 (edited) Then I don't know, mate, get another TV? Edited March 15, 2010 by Osbo 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 15, 2010 Author Share Posted March 15, 2010 (edited) Then I don't know, mate, get another TV? LOL! Already tried 3 different ones in the house. Paging A.J. Franzman, any ideas? Edited March 15, 2010 by A-T-A-R-I 1 Quote Link to comment Share on other sites More sharing options...
Koopa64 Posted March 16, 2010 Share Posted March 16, 2010 Maybe the TIA chip is dying or damaged somehow? 1 Quote Link to comment Share on other sites More sharing options...
A.J. Franzman Posted March 16, 2010 Share Posted March 16, 2010 Maybe the TIA chip is dying or damaged somehow? That's one possibility. Another (I guess) might be a power supply or filter capacitor issue. Really strange though, I haven't seen anything quite like that before. 1 Quote Link to comment Share on other sites More sharing options...
zylon Posted March 16, 2010 Share Posted March 16, 2010 (edited) being that it's a 6er, does it have the static strips in place? If not you can make them from foil tape. Also could be cracked wire in the MB to SB harness or ribbon cable. You seem to have terrible luck in picking systems so far Edited March 16, 2010 by zylon 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 16, 2010 Author Share Posted March 16, 2010 (edited) Koopa That's what I thought first was the chip was dying, so I changed all three. Zylon Yep, static strips are on. Also, this 6er does not have the ribbon cable. It is the multi colored wires with the brown connector. And you are right, I have TERRIBLE luck on these systems. I always think I am going to get a good one, but never happens. Now I have 5 that are not fully functioning. A.J Could the CMOS buffer chip (4th chip) be a cause of the problem? Not sure what that controls. Edited March 16, 2010 by A-T-A-R-I 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 16, 2010 Author Share Posted March 16, 2010 (edited) Here is some more interesting info. Been sitting here and pounding my head against the wall and thought hey, what happens in B/W mode. I switched to the B/W mode with the Circus cart in and while the screen works correctly and goes B/W, those lines that showed up in color mode in the pics above as being darker, are still there in B/W, but show up as very faint "rainbow"colors. Really strange. Also decided to change X200 colorburst crystal, nope, problem still there. Edited March 16, 2010 by A-T-A-R-I 1 Quote Link to comment Share on other sites More sharing options...
tetrode kink Posted March 16, 2010 Share Posted March 16, 2010 Do you have the big metal shield box still over the chips? If not, maybe some digital noise is creeping into the RF. -tet 1 Quote Link to comment Share on other sites More sharing options...
alex_79 Posted March 16, 2010 Share Posted March 16, 2010 Does it on all tvs in the house, but only using this console, so I am sure it is something with this console. Here are some pics, not that great. Really strange. When you turn the paddles, you can see movement within the darker area going up and down. I have the exact same issue with my 7800, but it's a lot less visible with my console than on the screeshots posted by A-T-A-R-I. It's a PAL-B version and it has composite video out. The effect is the same using the real cart or the rom loaded in the Harmony. I can't say if the issue was there before the A/V mod, because the rf modulator didn't work when I bought the console. 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 16, 2010 Author Share Posted March 16, 2010 Do you have the big metal shield box still over the chips? If not, maybe some digital noise is creeping into the RF. -tet Yep, it's on, with the bottom too. 1 Quote Link to comment Share on other sites More sharing options...
zylon Posted March 16, 2010 Share Posted March 16, 2010 the channel select switch can cause some on screen problems if it's dirty inside. is this the only game this happens on? 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 16, 2010 Author Share Posted March 16, 2010 the channel select switch can cause some on screen problems if it's dirty inside. is this the only game this happens on? Happens on Combat, Home Run, Circus, etc. Seems like anything with a green or blue background. 1 Quote Link to comment Share on other sites More sharing options...
A.J. Franzman Posted March 16, 2010 Share Posted March 16, 2010 I switched to the B/W mode with the Circus cart in and while the screen works correctly and goes B/W, those lines that showed up in color mode in the pics above as being darker, are still there in B/W, but show up as very faint "rainbow"colors. Really strange. Also decided to change X200 colorburst crystal, nope, problem still there. If you're getting color in B&W mode (on a game that has a true B&W mode), it can only be the TIA or instability in the color circuit. It's possible that you were close with the crystal, but I believe the transistor or capacitors would be more likely. If I had that console here though, I would try swapping the TIA first, just because I have them handy and it's an easy check. 1 Quote Link to comment Share on other sites More sharing options...
A-T-A-R-I Posted March 17, 2010 Author Share Posted March 17, 2010 (edited) I switched to the B/W mode with the Circus cart in and while the screen works correctly and goes B/W, those lines that showed up in color mode in the pics above as being darker, are still there in B/W, but show up as very faint "rainbow"colors. Really strange. Also decided to change X200 colorburst crystal, nope, problem still there. If you're getting color in B&W mode (on a game that has a true B&W mode), it can only be the TIA or instability in the color circuit. It's possible that you were close with the crystal, but I believe the transistor or capacitors would be more likely. If I had that console here though, I would try swapping the TIA first, just because I have them handy and it's an easy check. Already swapped the TIA and the other chips when the issue first started, but no changes. The colors in B/W mode ARE VERY FAINT, but you can still see them, just where the darker lines are. Which transistor or caps should I check? Thanks for the help. Edited March 17, 2010 by A-T-A-R-I Quote Link to comment Share on other sites More sharing options...
A.J. Franzman Posted March 17, 2010 Share Posted March 17, 2010 Could the CMOS buffer chip (4th chip) be a cause of the problem? Not sure what that controls. The CD4050 buffers the joy fire button inputs (2), the TIA luma outputs (3), and I forgot what the sixth channel buffers... probably the video sync. If both your joy port fire buttons work, and you get a nice 8-level shading of the sky in Air-Sea Battle/Target Fun, that chip should be OK. Quote Link to comment Share on other sites More sharing options...
A.J. Franzman Posted March 17, 2010 Share Posted March 17, 2010 Which transistor or caps should I check? The ones right by the crystal. From one of the schematics in the service manual, I believe Q200, Q201, C202, or possibly C203 or one of R200-R205 could be at fault. Quote Link to comment Share on other sites More sharing options...
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