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303george

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Hello! I'm wondering if anyone can give me some pointers on a few issues I'm having with this monitor.

* I have some horizontal pinstripes (monitor is in vertical orientation in a centipede cabinet so they appear vertical on the screen but in actuality I think they'd be considered horizontal).

* Slight warping/misalignment of some of the images on screen.

* A sort of jagged line across the top where you can see that the image isn't displaying above but is displaying below

* lots of empty space at one side (which appears to the the bottom since the monitor is rotated 90 degrees) basically there's a big blank area below the area where you can move at the bottom of the screen and I can also see some old burn-on where the Atari copyright is but the actual image of the copyright text is well above the burn in so it appears as if everything is shifted upwards. If I'm not mistaken, I think there are some pins/jumpers or something on the board that adjust the orientation and I'm wondering if I should try messing with those, if anyone can confirm the correct jumper setting for Centiped, and whether or not I should discharge the flyback/annode before I mess with the jumpers or if it's ok to leave it and just be careful.

I've not been able to get rid of any of these issues by adjusting the pots but I don't remember seeing the pinstripes until I started messing with the pots. However, I also don't have a mirror right now that I can use to watch the monitor while I make adjustments so having to make slight adjustments and then check the result until I can get a mirror.

A little bit of back story on this monitor that might help determine what the problem is - Initially it was just showing a pulsating green blob in the center of the screen. I recapped it and replaced the HOT and flyback but I installed the new HOT incorrectly and shorted it out which resulted in no image at all. After that, I found that the fuse near the big cap on the chassis appeared to be blown (it didn't look burnt but the tiny little whire inside seemed to be broken). Also the big cap was still holding a charge after I had discharged the flyback/annode and when I bridged the + and the - on the big cap with a screwdriver it let out a huge pop and spark. I replaced the fuse and reinstalled the old HOT, making sure to correctly install it this time and I finally had picture but I now have the issues above. I don't know if the issues were present before doing the work because the monitor wasn't working when I got the cab.

Could these issues all be related to the old HOT needing to be replaced or is it more likely that I damaged some of the new caps or other components when I shorted the New hot or when I discharged the big cap? Would a yolk adjustment help? Any insight would be much appreciated. This is my first time ever working on a CRT so if you couldn't tell already, I'm no expert.

I got one decent pic showing some of the issues. Note that the screen actually extends a bit up above that line at the top where the image ends and also note the copyright text up above where the burn in is (which is where I'd guess the image really should appear). You can also see the pinstripes and if you look closely you can see some of the slight warping which appears mostly near the top and bottom of the screen.
 

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those are flyback lines.
reduce the brightness using the control on the line-output transformer till they are gone.
then adjust the focus control - because the 2 effect each other.

then adjust the brightness of the 3 colours using the RGB controls that if i remember right are on the neckboard.

btw, that's not a fault - you just dont know how to setup a crt monitor.
well - now you do! :)
 
those are flyback lines.
reduce the brightness using the control on the line-output transformer till they are gone.
then adjust the focus control - because the 2 effect each other.

then adjust the brightness of the 3 colours using the RGB controls that if i remember right are on the neckboard.

btw, that's not a fault - you just dont know how to setup a crt monitor.
well - now you do! :)
Thanks! I think I know the transformer pots you're talking about and come to think of it, I didn't even touch them. Between the excitement of finally getting the thing working and the other nine pots I totally forgot about those other two. You're right about the RGBs. I did mess with those a bit on the neck board.
 
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