Okay. I got a beefy film cap and replaced it and it fired right up.
After running it for awhile and doing some setup, the Vertical started to go, and I found that the capacitor between the pump-up pin and the output power supply on the vertical IC had blown.
This would not be a surprise to me, except that I already replaced that capacitor with a good Panasonic cap. This time I also replaced the 7830 vert IC because I have one in parts bin.
I was able to more or less dial in the purity and convergence, but I'm having some weird issues on the screen still:
1) I'm getting this effect where the top and bottom of the screen are kind of pinched inward.
Usually, if either the top or bottom is pinched in, the other side is bowed outward, indicating that the yoke is tilted. In this case though, both the top and bottom are pinched inward, so I don't know exactly what that means.
2) Horizontal linearity is still messed up. If I display a row of circles across the raster, the circles on the left side of the screen are correct, but the circles on the right side of the screen are horizontally squished. This is especially obvious in test patterns. This isn't a new issue, it was like this before the bipolar cap on the horizontal yoke blew up.
Anyone have an idea as to these two issues might be caused?