Geometry issue on MS-2931 - map/pictures of board needed :)

[Gonzoide]

Hi all,

I have a little geometry issue on my Blast City (MS-2931) : top of the display is straight, but not horizontal (lower on the right hand side), so the image is not rectangular.

Factory menu does not help, as Parallel and Trapeze settings apply to the horizontal dimension, not vertical.

I saw on a french forum that a guy had similar issue : apparently he eventually found a potentiometer on the motherboard that fixed it, but that was 3 years ago and the guy is gone, so I don't have a clue as to where this setting is. I took as many pictures as possible from my board without taking the monitor out, but with no luck so far.

So if anybody had pictures of potentiometers onboard the MS-2931, or new which one I should tune, that would be very helpful ... thanks.

[nem]

I don't think there are pots on the chassis.

I had a similar issue that I fixed with a magnet strip that I salvaged from an old broken monitor.

[Gonzoide]

I'll have to play the magnet strip game anyway, I have a little convergence issue I'll want to deal with. What this specific default difficult to fix ?

I read somewhere that the magnet strips did not actually contain magnets but rather a piece of metal, could you please confirm ? Thanks.

[nem]

Those are yoke tabs. They're good for fixing convergence. Can't remember what they're made of, but you're right, they're not magnetic.

However if you want to fix a larger geometry related issue, you want magnetic strips. I've seen them described as chevron or sergeant stripe magnets. They look like this /\

[Gonzoide]

So I have to get those two flavors of strips to fix all of my issues ? Damn.

From what I've found on internet I think I can handle the convergence part, but I've never seen anything about out to use those magnetic chevrons, would you have any link ?