MVS U4 Toei Chassis (33 inch) switch function / schematics

[Moonwalker]

Hi guys,
I hope someone can help me out. I finally recieved the cab and sent the chassis to a friend who recaps it.
There is a problem with blue and he asked me if I can get the schematics.
Also it seems there is a switch next to the RGB part, anybody an idea what the function is?
Thanks!

 

[nem]

Also it seems there is a switch next to the RGB part, anybody an idea what the function is?

I think it has something to do with horizontal sync. The picture shifts left and right when you switch it. On the chassis it's labeled "pedestal" (porch?).

 

[Moonwalker]

I think it has something to do with horizontal sync. The picture shifts left and right when you switch it. On the chassis it's labeled "pedestal" (porch?).

Thanks Nem. Can you tell me what the default position is?

 

[nem]

I have it set to middle position.

 

[Moonwalker]

I have it set to middle position.

Thanks!

 

[Moonwalker]

I think it has something to do with horizontal sync. The picture shifts left and right when you switch it. On the chassis it's labeled "pedestal" (porch?).

Seems the switch is a voltage divider for the RGB signal. If someone else is wondering what it is in the future.

 

[nem]

I've heard this too, but if it was one, then why doesn't it affect brightness?

 

[Moonwalker]

As I heard from my friend it does.

 

[nem]

You were right, I was wrong. I flipped over the chassis and there is indeed a resistor array that connects to all video lines: red, green, blue and sync.

No idea why I'm not getting any difference in brightness with a PGM. The picture just jumps around when I use the switch.