Techman

Sanyo AVM 3689G that went dead or "black screen" that you gave me advice on July 28th. I had a TV service tech come over and two younger techs showed up, neither of them looked comfortable with this model. One even admitted that he usually doesn't work on these types of TV's. Anyway, they checked the fuse on the main power supply which checked out ok. They visually checked some of the capacitors which they said "looked good". Then they said that the main power supply board is bad which will cost several hundred dollars to fix. Is this legitmate or did I get hosed. The only item they tested with a meter was the fuse, nothing else. Can you determine the problem without testing components? Help!