Guys!
If the yokes are positioned and aligned correctly on the tube necks then such problems can be minimized; perhaps the unit had been retubed without full attention to details; one also has to confirm that rasters are centered with all convergence nulled, and a few other things:
The yokes belong as follows: Scan yoke in front of course, be sure any original hot melt glue is removed from inside it; it must go as far forward as possible. Align the scan yoke for a level horizon with zone convergence nulled.* The second yoke is convergence and yours might be glued to the scan yoke; the convergence yoke is aligned so zone adjustments go straight up/down, no skew. Since the scan yoke has no clamp you want to hot-glue it to the convergence yoke, which does have a clamp. The third larger yoke is focus and stig, if you loosen the brass fasteners it can be wobbled about the tube neck and acts like a centering magnet and affects flare considerably; it has a clamp in back and a second clamp inside a small access hole; when correctly aligned you would have a centered raster on the tube face with static convergence nulled, and correct flare adjustment also. The rear-most yoke is flare; it is aligned by looking at defocussed dots and set so the hot-spot is centered in
the middle of the fog. To align flare correctly, select 31khz from internal frequencies (UTIL 1, 6, 2) the # for dots only, then Color 1, Color 2, Color 3 for one color at a time. Put PIC, 4 focus to 0, and contrast to 80-90, then rotate the flare magnet knob about the tube neck and also turn the knob in its' place for best alignment. When finished you should have a centered raster with static convergence nulled, for all three colors. Now confirm that all three crosshatch grids are centered on the screen; if not, then mechanical toe-in may need adjustment for red and blue; if green is not centered on the screen then the entire
projector needs to be aimed. Stig adjust is done in the Service Menu, UTIL, 9, 0901, 7, with 31khz as above but focus shoved to 100, 80+ on contrast. Set all dots for round. 31khz is preferred for bigger more visible dots. Also remember to match raster heights in the service menu, this is selection 3. Widths are matched with a plastic slug coil tool used to turn the width coils atop the horizontal sweep board, located in between the green and blue CRTs. The two front-most coils are for red, the front one is for below 60khz (low band sweep), the second coil is high-band or above 60khz) The middle pair is for green, same layout for
bands, rearmost coils are for blue. Finish up with zone focus (Service, 2) and geometry correction as needed, convergence and gray scale setup.
* To null static convergence only, push CONV, 1, 1; push CONV 1, 2 to null zones only; push CONV, 1, 0 to null both. That is for red and blue; for green push CONV, 5, 0901, and then push 2 and then 1, 2, or 0 as above. If you are working in a locked memory then you will recover your original settings next time you select that memory. I hope to have this and other useful information available soon on the E-Tech website which is undergoing total redesign.