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AppleColor RGB Monitor issue

raoulduke

Well-known member
Unless I set the horizontal basically all the way from edge to edge of the CRT, it flickers with almost a frequency-pattern, like one would expect on an oscilloscope, but I can tell/here/partially see that the machine is chugging away and that this is purely visual.  There's a minor buzz, as well (most audible from above).  Finally, when the horizontal is all the way out and I get a sort of stable picture, on the right you can see that there's a vertical "misalignment."  The first and last rows don't fill out all the way, and on the top, beside that stump-row of blue, you can see several black rows that I'd describe almost as analogous to the weird spacey green pattern on TRS-80s when the A/Bs start to die, but in this case much more compact and the rows are not spaced out (between them).  Just to be clear, if I try to adjust the horizontal (etc.) to get rid of those stump-rows, it resorts to the static/frequency patterns.  I can't get a good shot of that, though.

Any thoughts?  Have I missed a thread already on this?

[Though I didn't think about it initially, I might have put this under earlier Apple, but since the AppleColor RGB Monitor could also be used on the Mac II with the hi-res card maybe it does best belong here anyway.]

 
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raoulduke

Well-known member
Deflector Board D?  I'm planning on eventually taking the thing apart but I'm really not sure what to look for.  This doesn't fit one of the troubleshooting templates and most of those (particularly the most analogous - which aren't that close) involve eventually or initially replacing that board.  There's one on eBay for $40, but I'm not sure it's not worth just waiting until I come across another monitor.

 

techknight

Well-known member
The picture is pretty shitty so I cant really tell, but that looks like a logic issue. Deflection circuitry wont do that without tearing the entire image. 

 
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techknight

Well-known member
I am not really seeing anything wrong with the CRT. its perfect. If your talking about the quarter long blue line at the top before black, thats logic board failure. If you look at the bottom, its the opposite. Same length. Again, issue in the graphics chip somewhere. 

 
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raoulduke

Well-known member
Alright thanks. And this is my attempt to capture what happens when one tries to reduce horizontal control. 3rd pic is horizontal increase. 4th is middle vertical control at max. And 5-6th are leftmost vertical control.

Sorry, I'm installing Windows 2000 or I'd rotate all the pics; I apologize for that.

 
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CelGen

Well-known member
I see horizontal sync problems, vertical linearity problems and what looks to be more sync problems. You have at least one cap that is sitting at its tolerance due to age.

 

raoulduke

Well-known member
Okay. Recapping I can do. As I say, at some point after the novelty of playing with the system wears off (after I can figure out networking) I'll open it up; my plan was basically to look for cap issues, bc I don't know how much else I can do.

 

CelGen

Well-known member
Well failing a cap issue there's a serious issue with the sync signal coming out of the IIgs but I don't think you have another monitor to test with, right?

 

techknight

Well-known member
See, these pictures are WAY different than the first ones you posted. These pictures are actually showing issues. 

The horizontal is going to do that, When you adjust horizontal, your adjusting the lock frequency which does exactly that. thats normal. 

The vertical line in the top looks as if you are adjusting the vertical linearity control? Or does this change while its running? get better, get worse? Vertical issues are very common. Horizontal issues are NOT. 

 
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raoulduke

Well-known member
As I noted in a PM, those are rotated 90 degrees counterclockwise; so I think the vertical line you're referring to is the line below "Check Startup Disk," which is horizontal.  So then it sounds like I have uncommon vertical issues and not really common horizontal issues, then?

 

techknight

Well-known member
Im looking at the line ABOVE the check startup disk. 

Anyways, your messing with the horizontal and vertical controls so your going to get that effect on the screen corresponding to each control. 

Im still confused as to what point your trying to demonstrate/prove? 

 
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