Motorola TS 18 horizontal issue

[DavGoodlin]

The original 7JP4 was gone, National Union (NU) made 8BP4 was found and it makes a decent but somewhat dim raster, there is no ion trap on electrostatic tubes, hence they test ok but dim due to phosphor degradation. Sound and video stages are OK. Vertical sync is OK, sweep size ok.

Current Problem: Horizontal too touchy, was able to get it "locked in" with a wiggle in the picture, now the width is decreasing and it won't lock then "xmas trees" out. The Sync clipper, AFC and Horizontal osc is two 12SN7s and two "blocking" interstage transformers and wonder if something besides tubes and capacitors*. Need to check voltages but was there an "old" thread on these?


*I recapped the chassis and rebuilt the ballast using sand blocks and ceramic log power resistors and diodes similar to Bob Anderson's thread, so no issues there and supply is B++ is 270v. I had three other JFD nib ballast replacements that also had corroded rivets on the "mica toaster panel", were thus useless