I have restored an SE. After recapping the analog board, and going back today to replace CR2 and Q2 b/c the Dead Mac Scrolls described a symptom that might have been this one, I haven't resolved the final video issue.
The video is solid, but at unpredictable intervals the entire screen increases in width, just for a few frames. Sometimes this happens repeatedly over a few seconds, other times it's a one-off, and it usually doesn't repeat for a couple of minutes. Given that it's a machine from another millennium, it's still completely acceptable and usable. But I'd luuuuv to iron out this final wrinkle. Oh, I should clarify: this was happening even before I recapped the analog board. It was why I recapped the analog board.
Anyone have advice?
(The raster also appears to not be centered horizontally, but, I could let that slide.)
I have done a full recap of the logic and analog boards (including C15 on analog). The system was in pretty good shape, with no signs of leakage or battery death.
Video attached. The scrolling horizontal bar is not visible to the eye and is a camera-capture artifact. Look for the raster to just momentarily be wider at 0:05s .
View attachment IMG_5488.mov
The video is solid, but at unpredictable intervals the entire screen increases in width, just for a few frames. Sometimes this happens repeatedly over a few seconds, other times it's a one-off, and it usually doesn't repeat for a couple of minutes. Given that it's a machine from another millennium, it's still completely acceptable and usable. But I'd luuuuv to iron out this final wrinkle. Oh, I should clarify: this was happening even before I recapped the analog board. It was why I recapped the analog board.
Anyone have advice?
(The raster also appears to not be centered horizontally, but, I could let that slide.)
I have done a full recap of the logic and analog boards (including C15 on analog). The system was in pretty good shape, with no signs of leakage or battery death.
Video attached. The scrolling horizontal bar is not visible to the eye and is a camera-capture artifact. Look for the raster to just momentarily be wider at 0:05s .
View attachment IMG_5488.mov
and now they require one.
) to verify the issue. The screen looks like it is getting wider on the right, but is pulling in on the left. It looks like the linearity of the image is shifting. The datasheet shows that the linearity is controlled by adjusting the the resistance in the voltage devider between pin 12 and 10 (the two 68k resistors). That signal then goes into the pre-amp. Since macs don't have a vertical linearity adjustment this is a set value on these monitors. Having never seen this issue on a mac before I'm postulating, but I have seen vertical linearity issues on other monitors that look very similar to this. I would check that area for any solder cracks (i'd reflow everything in that area), parts that seem out of spec (check when cool, and after they're hot), and check the pads/trace leading from anything you have soldered on. Sometime you can cause the pads to fracture from the trace and they can be intermittent. Worst case I'd replace the tda1170 to see if it's starting to fail. I would do that last after verifying all supporting parts were 100%
