[Username1]

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Hi - Well it looks like a shorted cathode to G1 inside the picture tube, or shorted driver
transistor for the blue gun. If the transistor & other drive voltages look ok, and you
have re-flowed solder on any connections that look like they need it, the next step
is to get a nice wooden dowel and start hitting the neck of the picture tube and
see if it's sensitive to being whacked. Next is to do the same with the neck
board, and then on the main board. On the main board you can also push
on different points on the board, "point pressure" to see if that's a point
where you need to inspect solder joints.

Now when you hit the picture tube, I mean use the point, and hit the
tube with the point directly imparting the force at a specific point on
the neck. Impact it with light force, then more, don't hit it side-stick.
Tapping = hitting

To find intermittent connections, hitting stuff and finding the smallest
sensitive area is a good way to localize it. Good Luck.

PS Also you said it was going on for as long as you had it. Is it a time
sensitive thing, "been on for 30 minutes then it starts", etc., or is
it sensitive to being moved? that's a bad connection.

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