Quote:
Originally Posted by Alex KL-1
So the multiscan not operates correctly? We presume then the wrong auto setted voltages as a result.
What is the scan rate detector, a µcontroller or a bunch of logic IC's?
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A bunch of logic ICs and discrete components.
The Horizontal and Vertical Sync signals come in directly from the VGA cable to the Multisync PCB, while the color information is sent directly to the Neck PCB.
EDIT:
Ok, I managed to get the raster back to what I had last week where I can see the image, but I do not have (much) Vertical Position control. I have Vertical Size, Horizontal Size, and Horizontal Position, but Vertical Position is just a tiny little bit, and it's always basically too low down on the raster. I have no Pincushion controls (even less than when I first started).
I removed IC604, IC250 and IC302 and replaced them with new parts and just kind of did my best to reflow anything I had reworked and that made the raster come back.
I still have the problem with Zero Volts in the area beyond Pin 5 of IC604.
I switched the resolution to 1024x768 to see how that would change things, and I am seeing 18V on the base of Q317, which I don't think should be there. This connects to a Relay on the D PCB, so I thought maybe it's a problem on the D board, but I measured the Pin on the connector that goes out to the RELAY and it's around 4.3V while the Base of Q317 is 20V. It interacts with Q616, so I measured the Base of that and it's at it's correct 5.5V, so I don't think this is a problem over there.
I guess it must be all coming from the other side of the circuit?