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This is getting to be more involved than I expected.
I checked for residual magnetism in the yoke. The earth's field in Michigan should be about 0.57 Gauss. The field along any axis in the yoke was 0.5 Gauss or less so it doesn't appear to be magnetized. At least not enough to cause any problems.
The first photo shows the rear of the yoke. You can see the bottom h-coil is distorted. The second photo shows that it doesn't appear to be cosine wound. The third photo shows the ends of the coils not being perpendicular to the axix. I think these all add up to the bad focus issue.
If you look through the mounting slot you can see the iron wire that forms the core.
I shortened the leads on the yoke and corrected the reversed horizontal lead connection. The ringing is terrible.
After getting the right image by swapping the leads, the blue lead was not connected to the hot side as both the schematic says and the data sheets indicate. The horizontal output choke appears to at least had one lead lengthened. I don't think it's possible for them to have reversed the output leads and have it work at all.
As John Folsom mentioned, the coil that has the capacitor across it should be on the hot side, which it isn't now that I have the right image. I'll have to move it to the hot side and see how well it works.
The data sheet with the RAM yoke says that when they supply the network with the yoke it's not connected. In this yoke it was already connected. They also give instructions for balancing the yoke if there is still ringing after properly connecting the supplied network. If connecting the capacitor to the other coil half doesn't eliminate all the ringing I'll have to build their little "X" checker device. Just a variable resistor and capacitor in series.
I don't want to run the set while it's in this condition, so I'll take photos once I get it working better.
In spite of the ringing, the focus problem is still gone.
The yoke appears to have been made by Chicago. It looks just like their TY-1 yoke.
John
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