68kMLA Classic Interface

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IIgs Screen
Posted by: bibilit on 2017-03-20 00:14:53
trying to repair a IIgs screen, image is as picture... not seen anything obvious.

IMG_0884.JPG

Any idea ?
Posted by: techknight on 2017-03-20 14:38:06
Yep, capacitors associated with the vertical output IC, and the possibility of it being the vertical output IC itself. 

Also the flyback is known for seriously bad solder joints and if your missing one of the B+ scan supply rails, it can cause this as well. 

A strong smack in the side while on will wraggle that one out. 
Posted by: Johnnya101 on 2017-03-20 17:25:46
Yup, re solder those joints and GET NEW CAPS! They are all only rated to 85c and are all exposed to high temperatures all the time. Those monitors get hot fast...
Posted by: bibilit on 2017-03-22 00:32:56
Joints have been reworked, tried to hit while on, no better.
Posted by: Johnnya101 on 2017-03-22 04:26:48
I really think it's caps since you've got a partial vertical collapse and can see some of the no startup disk screen (Or something?).

On my other thread here there's a cap kit console5 is selling for $15. You get all new name brand caps, along with a peice of candy! Lol.
Posted by: techknight on 2017-03-22 16:16:24
Then you likely have a failed vertical output IC. 

A capacitor CAN cause this, but usually from my experience working on old tube type TVs is when the caps fail in the vertical output stage, it takes the IC with it. 
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