Luminance Issue ?

[jstout66]

I'm stumped....
Damn System 3 sets are too "new" for me, so if anyone worked on em in the day and saw this problem, can you point me in the right direction?
This is my 81 19" with Space Phone.
Last year some filter caps went out on the 9-160 board. Got that fixed and it's been working okay. Yesterday, turned it on, and it had a really dark picture, color looked maxed out as well. Screen would go back to normal intermittently. (picture looked like it was pulsing) To me, it looked like a luminance issue, like when a video tube went out in a tube set.
Would it be the board that plugs into the CRT?
This is one set I don't want to toss....
Zeno? Tom?