Mr. Do screen curl, Not monitor

Cmndr Brain

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I'm working on a Mr. Do board and have it working, mostly. After changing 4 bad 74LS161 counters and 3 bad 74LS74 flip flops and 1 bad 74LS107 flip flop, I finally have a working board except the screen is curling on the left side. I'm positive it is not the screen. In the images you can see the Mr. Do board curls on both LCD and CRT monitors, while a bowling game works on both. (yes, there is a slight curl on the crt, but not Mr. Do curl).
I have checked the counters again and the sync signals and all seem w/in spec. Any guidance and where to look now? Thank you.
First 2 images are LCD comparisons while 2nd 2 are CRT.
lcddo.jpg lcdbowl.jpg crtdo.jpg crtbowl.jpg
 
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Nobody? No, guesses? I'm thinking it's either another counter or a counter is being loaded with a wrong value.
 
I had similar with a 60 in one and it turned out to be the PSU causing the issue.
Well, I guess you're sort of correct. I have a switching power supply on my test rig. I turned down the voltage and the curl gets less and less until about 4v. At 4v the curl is gone, but the game no longer plays because the voltage is too low. So, now to test it with a different power supply or find what component doesn't like the higher voltage?
 
Well, I guess you're sort of correct. I have a switching power supply on my test rig. I turned down the voltage and the curl gets less and less until about 4v. At 4v the curl is gone, but the game no longer plays because the voltage is too low. So, now to test it with a different power supply or find what component doesn't like the higher voltage?
yeah that tells me there's a bad chip somewhere. you suggested something with counters, you replaced some previously? perhaps look around for Fujitsu parts or see if any are getting hotter than others. I have no idea about the anatomy of Mr. Do, perhaps Mark Spaeth can tell you specifically which bits are quarrelling with each other
 
You probably have the wrong sync configuration.
Look at page 17 of the manual.
I looked at that and don't think it's wrong. It's using the composite sync to both monitors. Still looking for any anomalies.
 
This is an horizontal sync problem. Dose adjusting the monitor H sync pot help? Check the horizontal counters on the pcb if the monitor adjusting dosen't do anything.
 
This is an horizontal sync problem. Dose adjusting the monitor H sync pot help? Check the horizontal counters on the pcb if the monitor adjusting dosen't do anything.
I'll check this out this weekend. The lcd monitor on my test rig, doesn't have any sync adjustments, but my test crt does.
 
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