Swapping a K7000 Chassis and K7400?

ArcadEd

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So I have a tube that is all scratched up. It has a K7000 in it.

I have a tube that looks great and has a K7400 in it, but currently isn't working. Is this a straight swap, or do I need to measure the yoke values to make sure?

Ed
 
Values

Test the yoke values just to be safe.. You should be fine, but I've found some of the value info online is not spot on, or sometimes correct.. Only takes a minute to test :)
 
Thanks guys. What's the best site to look up a walk through on doing the test. I did it several months ago for a donar tube, but haven't since.

Thanks as always. :)
 
a old school k7000 is nothing like a newer 7400...

however the tube does have the correct pinout, so cerefully ohm the yokes..

If the donor tune and yoke has the same or slightly higher readings itll probhably work.

If the donor tube/yoke ohms out at a lower ohm reading than the old one, youll be switching yokes and re-converging.

ohm both post your results here..
 
My notes say that the K7400 is H:1.4 V:8.2 and the K7000 is H:1.7 V:10.7.

That's pretty close, but in my experience having done two tube swaps on K7400s, in both cases the doner tube was within 0.1 ohm H and I couldn't get the focus perfect on either. I had to swap yokes as well.

You may as well give it a try, but if you just can't seem to get the K7400 to focus on the K7000 tube, you might need to swap yokes.


Edit: I got what you were doing backwards. Maybe you'll have better luck with the K7000 chassis then I've had with K7400s.
 
Last edited:
OK.

K7000 Tube
Horiz (red/blue) - 2
Vert (Yellow/brown) - 10.8


K7400 Tube
Horiz (Red/blue) - 1.4
Vert (Green/yellow) - 7.5

Dan, I was actually planning on putting the K7000 on the K7400 tube.
 
I'm assuming this is a 25" K7000, correct?

It's really easy to swap the yokes, and I'd do that. otherwise you might get some warping issues in the corners.

Also - don't forget that the K7000 needs an isolation transformer while the K7400 does not...
 
Interesting about the ISO, I didn't know that. I always tend to use one.

I've never done a yoke swap before, is it hard?

If I have to go that route, I might just find a Tube with no chassis and swap. Since the 7400 already had a board (although I don't currently know what's wrong with it as I await a remote board) maybe I will just keep it as that.

If it was a quick and easy chassis swap I figured what the hell :).

Oh, and yes. It's a 25"
 
The yoke can be swapped in about two minutes if you know what you're doing. You have to remove the rings first (mark their position so you can put them back exactly), then remove one yoke, install the new yoke, put the rings back on - then use the new chassis.

There are plenty of tube swap threads around with pics and more detailed info...
 
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