Compatible chassis list?

dkblue

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Hi again,

Is there a list for what chassis are compatible with each other? I'm not sure I'm asking this correctly...

Basically, I have my monitor problems with my 25" monitor in another thread, but I also have several other dead 19" Wells Gardner monitors. So I'm curious if I get one chassis going, can it be stuck on another tube that has less burn-in?

Thanks!
 
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The key thing is the yoke.
you can do a tube swap if you either have the SAME (or very close values) yoke, or you move the yoke that goes with the working chassis.
If you have to move a yoke expect to reconverge unless you are really really lucky with the rings being in the exact same position.
 
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This may be a dumb question, but is there a compatible yoke and board list then? Or is it something that's on a monitor by monitor basis?

The key thing is the yoke.
you can do a tube swap if you either have the SAME (or very close values) yoke, or you move the yoke that goes with the working chassis.
If you have to move a yoke expect to reconverge unless you are really really lucky with the rings being in the exact same position.
 
I've seen some user made lists here and there, nothing complete though.
I know there are complete lists for the service professionals but I'm afraid I don't know what they are called.
I'm sure someone will chime in here, as there are a couple other caveats to swapping tubes as well like the degree tube, etc..
 
Yes, there are places to find what yoke matches what chassis. It's called a monitor manual.

For example, if you have a K4600, you can look in the K4600 manual and get the part number for the yoke. Unfortunately, that won't help you much if you're trying to match the chassis with a different yoke.

You see, the important part of a yoke working with a chassis is the yoke winding readings. Each yoke is actually two yokes - a horizontal and a vertical. Each yoke has a resistance value that needs to be in a specific range so that it will operate properly when receiving a specific voltage from the chassis. if you try to hook up a yoke with a resistance value that is too low or too high, you'll either blow up the yoke (and maybe your chassis as well), or at best it just won't work.

Now, there are a few incomplete lists of some common chassis and the yoke readings they expect, such as this one:

http://www.vidiot.ca/montube.php

If you have a yoke that you want to try, you need to measure the resistances on the horizontal and vertical yokes, then see if it is very close (within 2 ohms is best) to what the chassis requires....
 
And it's actually not just resistance, but inductance that makes the yoke geometrically / fully compatible. Measuring resistance (DC voltage) gets you 'in the ballpark' and prevents you from blowing up the chassis/yoke. However it's inductance (AC voltage) that really matters, and two yokes with identical resistance can have significantly different inductance and as such one may have strange geometic problems such as pincushion, trapezoid, corner tearing and the like that cannot be adjusted out.
 
Well, I suppose I could go digging through some pdf manuals if I can find them. But this is the age of the internet where everything has been referenced, cross-referenced, and the cross-references have been cross-referenced. :) I was just hoping there was something easier.

But that's good information. I have a better starting point now. Thanks...
 
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