Alpine Ski Screen Inversion

joseph77

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I did some monitor shuffling last night and threw a K4951 in my Alpine Ski. When powered up the screen was flipped. When I turned the dip switch (number 7 to on for screen flip) it corrected the problem but now the joystick/buttons controls do not work. Has anyone had this happen or know what the problem may be?
 
Looking at the manual, I think that switch is for a cocktail model and just changed the controls to the Player 2 set. Flip it back and invert the screen by flipping the yoke wires.
 
Looking at the manual, I think that switch is for a cocktail model and just changed the controls to the Player 2 set. Flip it back and invert the screen by flipping the yoke wires.

I figured I would have to do that. I just posted in the monitor section. It has a K4951, I think I know how to do it but am really not 100% sure. Any advice?
 
I figured I would have to do that. I just posted in the monitor section. It has a K4951, I think I know how to do it but am really not 100% sure. Any advice?

Green and Yellow are for Vertical Deflection, Blue and Red for horizontal. Since Alpine Ski is a vertical game, and the "cocktail" switch fixed it, I'm assuming this is a vertical inversion problem. A vertical monitor is rotated 90deg, so you will actually need to flip the horizontal.

The yoke connector is 4 pins and keyed. You will be (carefully) cutting the connector between wires creating two halves, yellow-green and blue-red. Before you do, make a note of how they were installed, because after cutting you can reconnect them incorrectly. Once cut, put the Y-G back like it was, and flip the R-B pair. That's it.

Note: You can flip Y-G and R-B alone or together to fit any orientation. But don't swap Y-G with R-B as the impedances of those loops are different can cause monitor damage.
 
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Instead of cutting the wires, the pins can be removed from the connector housing and re-inserted swapped. It'll take a tiny screwdriver and a little patience to find and depress the release tab of the terminals...
 
Instead of cutting the wires, the pins can be removed from the connector housing and re-inserted swapped. It'll take a tiny screwdriver and a little patience to find and depress the release tab of the terminals...

Great suggestion. Doing it Darren's way eliminates the possibility of incorrectly connecting the yoke after the mod is made. For those who choose to cut, please not that you should cut the plastic connector and not the wires.
 
Green and Yellow are for Vertical Deflection, Blue and Red for horizontal. Since Alpine Ski is a vertical game, and the "cocktail" switch fixed it, I'm assuming this is a vertical inversion problem. A vertical monitor is rotated 90deg, so you will actually need to flip the horizontal.

The yoke connector is 4 pins and keyed. You will be (carefully) cutting the connector between wires creating two halves, yellow-green and blue-red. Before you do, make a note of how they were installed, because after cutting you can reconnect them incorrectly. Once cut, put the Y-G back like it was, and flip the R-B pair. That's it.

Note: You can flip Y-G and R-B alone or together to fit any orientation. But don't swap Y-G with R-B as the impedances of those loops are different can cause monitor damage.

Hey thanks I will do this. It seemed kind of simple that is why I figured I should ask first. Do I need to discharge the monitor before doing this?
 
On second thought, go with Darren's suggestion. Much cleaner and easier than cutting. I'll be doing it his way from now on. Someone once told me to cut, and that's what I've done ever since without even thinking... :facepalm:

A discharge is not necessary. I discharge anytime I'm working on a CRT because it takes 5 seconds, but it's overkill.
 
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Great suggestion. Doing it Darren's way eliminates the possibility of incorrectly connecting the yoke after the mod is made. For those who choose to cut, please not that you should cut the plastic connector and not the wires.

On second thought, go with Darren's suggestion. Much cleaner and easier than cutting. I'll be doing it his way from now on. Someone once told me to cut, and that's what I've done ever since without even thinking... :facepalm:

Well, it's not easier than cutting, but it looks nicer. It just makes it a pain in the butt to change back quickly if you need to.

And you wouldn't have a possibility of incorrectly connecting the yoke after cutting them if you only cut between the Blue and Yellow and leave two halves. The spacing between Red and Blue is wider than between Yellow and Green, so you can't accidentally connect them to the wrong pins...
 
Ok so I swapped red & blue. The screen comes up properly but everything is spelled backwards. Any thoughts?
 
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