Picture flickers off and on

I would try adjusting the screen control on the flyback. The flyback can be easly located, find the red wire attached to the top of the picture tube & follow it down to the flyback. on the flyback you should find two controls, one screen & one focus. you sould be able to read the words above each control, only adjust the screen one. slightly increase the control till the picture stays on, if you turn it too much you will get small white lines going across the screen. Now if what i have told you fixes the set, then it is only a tempoary repair. could last days or mothes, maybe years. if it starts to happen again later the set will have to be replaced. this is a sign of the picture tube starting to get a weak. ALSO DO NOT PLAY WITH THE RED WIRE IT CARRES VERY HIGH VOLTAGES EVEN WHAN UNPLUGGED FOR DAYS.