the 3 'paint tubes' (green, red, blue) were replaced 4 years ago.
Problem: TV turns on, Picture comes on for a split second then screen goes blank. Audio always works.
I've noticed that after the TV has sat for a while and I turn it on, no picture at all comes up. But if I turned it on again right away the picture works for a split second than goes blank again.
No expert, but mine did close to the same thing. Turned it on one day and about a minute later it lost all picture but audio still worked. The color guns looked like they weren't getting any power. Repairman said problem is in the power supply board...possibly the flyback. It's not fixed yet. Was hoping it would be finished by today. The shop is also replacing the coolant fluid in the guns too. Will be costing me around 400.00 for everything. I know it's 14 years old, but the repair cost is only 22% of the price of a comparable set.
BTW mine is a '90-91 Magnavox (Philips) model RL8570AK08, 61".