Help with 9T246 Horizontal Linearity

[dtvmcdonald]

The saga continues!. I am letting it cook an hour a day. Last night the
picture started shrinking and then jumping back. Today
it started jumoping into severe horizontal ringing, then shrinking horiontally
but expanding vertically, then going dark, and in a minute or two coming back.

This was traced to the 6.8k HOT screen resistor, one of the few
old style 1940's (2 watt or so) power resistors left. When removed
and tested with an ohmmeter it was open, so it must have been arcing
internally. Replacing it fixed the set.

Is this sort of cook-and-fix par for the course?

Doug McDonald