Please help ID this chassis - need to check B+ voltage

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Please help ID this chassis - need to check B+ voltage

Hopefully this isn't too much of a long shot. Hoping someone out there is familiar with this chassis and can ID it just from looking at it. I have 3 main concerns/questions:

1) Where is the test point for B+ voltage?
2) There are R,G,B POT's on the chassis labeled R GAIN, B GAIN, G GAIN. Is this equivalent to RGB drivers or cut-offs?
3) There are R,G,B POT's on the neck board labeled R-BKG, B-BKG, G-BKG. Is this equivalent to RGB drivers or cut-offs?

Not sure if the following is relevant, but I offer it anyway. It's a standard JAMMA cabinet. Currently running a MAME computer w/ ArcadeVGA->JPAC->JAMMA output. I also have a NAOMI installed in the cab, and sometimes swap the JAMMA connector over and plug in the NAOMI kick harness, to play NAOMI games. Have also run standard CPS-1 and CPS-2 as well as other games in the cab.
 

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Okay, getting somewhere. On a hunch, I pointed my camera up toward the back of the chassis, from inside the control panel. Bam, found the part number. Wei-yah 826hr. Don't see a manual online anywhere. Can anyone help with where to test B+ voltage, and what the "gain" and "bkg" RGB pots equate to on a K7000 chassis (I have great instructions for white and color balancing, which refer to RGB drivers and cutoffs).
 

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bump. Any help guys? I'm needing to know what B+ voltage should be set to on this chassis.
 
Thanks, Ken. I did find the model number on the back of the chassis (see pictures above). I'm unsure of what B+ voltage is supposed to be set to, though. I'm probably being dense. I see on the schematic that VR104 adjusts it, but I'm not clear on what B+ should be set to for this chassis.
 
Well, I increased the B+ voltage pot slightly and the image increased in size vertically and horizontally. I increased it some more, and the image increase some more. I was able to dial back V SIZE and H WIDTH. I'm guessing B+ voltage was low, but didn't want to increase it any more, since I don't know where it's at or where it should be at.

That aside, I checked the neck board on a non-working 25K7193 that I've had sitting around for a while, and it's a perfect fit on the tube with the Wei-Yah chassis. Thinking about reviving the 25K7193 and replacing the Wei-Yah with it. Is there anything else that needs to be checked, to know that the 25K7193 will work with the tube?
 
Well, I increased the B+ voltage pot slightly and the image increased in size vertically and horizontally. I increased it some more, and the image increase some more. I was able to dial back V SIZE and H WIDTH. I'm guessing B+ voltage was low, but didn't want to increase it any more, since I don't know where it's at or where it should be at.

That aside, I checked the neck board on a non-working 25K7193 that I've had sitting around for a while, and it's a perfect fit on the tube with the Wei-Yah chassis. Thinking about reviving the 25K7193 and replacing the Wei-Yah with it. Is there anything else that needs to be checked, to know that the 25K7193 will work with the tube?

i would say only the yoke and you can ohm out the vert. and horz. wires of the yoke connector and see of they are within specs to match a k7000.
 
i would say only the yoke and you can ohm out the vert. and horz. wires of the yoke connector and see of they are within specs to match a k7000.

What is spec for vertical and horizontal resistance, for the K7000?
 
k7000 25 inch is usually about 6.3vertical 1.9horiz. you don't have be exact but close and you may have to change the width cap to make the image larger or smaller if your reading are off from original. i stock the width cap kits it you need them.
 
Okay, measured with the cabinet off.

red/blue - 2.1 ohms

green/yellow - 6.8 ohms

Thoughts?
 
That should work just fine. May not even need to fiddle with the width cap there since the readings are so close.
 
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