Do a google groups search here for ctc169 and ptk169 and make note of
all suggestions.
Power supply capacitors and diodes are a common issue, get the
locations c4104,c4102,c4108,cr4118, etc and make not of all of them.

There is also a link to download the general ctc169 schematic posted a
short while back.

Then look for the luma buffer transistor and plan on replacing it, I
think Q2906.
Good possibility it failed due to a picture tube arc back, in which
case it may fail again.

Very important that the standby B+ voltages, 145V and 15V, are exact or
several future failures will be expected soon.