I spent part of this evening pulling the sweeps board from the bottom of the Singer TV6U that seemed to be the most promising (I have two...one with a completely dead tuner/IF something or other)
I replaced all the 50uf caps with 47uf/50v electrolytics, and went from a VERY narrow folded over vertical...to this
I got to the point I can get a full raster...GREAT tuning (even the UHF module underneath). Already has great brightness and contrast. I had to replace a 10uf cap to get the horizontal hold "range" to adjust properly. I was able to get a steady lock before replacing the little 10uf, but the H.range had to be cranked ALL the way to one side before.
Now....All I hafta do is figure out why I have this small linearity issue. I can get decent linearity....or full vertical, but can't seem to get both yet. A full raster results in it spreading out towards the top (as seen in the test pattern). This is of course hardly noticeable with a moving picture...and is PLENTY watchable, but I saw someone post a TV6U restore that got PERFECT geometry....so I know it's doable. (I gotta find that thread again).
As you can see in my sig....I'm actually very proud to get one of these going finally. Any specifics will be GREATLY appreciated if you have worked on these before. I do have the SAMS (Set 806 Folder 4)...and it was quite helpful in locating what values of caps I had to work with. I was not able to find 50uf caps easily...so for now I am using 47uf ones....because they seemed closer than 68uf. I only so far got to the bigger cans...because almost ALL of them showed open.
Please excuse that the pics are a bit strange. My flat isn't very well lit at night...and the JVC Everio camcorder seemed to like the contrast and brightness REAL low on the Singer to get any sort of pic of the CRT (for the most part unwatchable....but able to take a pic of it). Notice the "egg shaped" test pattern showing I still have a linearity issue to figure out.