Sony VPH 1001 QM power supply problem

Hello from the South of France.

Well, after many years of faithful service, the blue tube on my VPH 1001 QM recently began to play up. Flickering and out of focus image. I have another unit for spares and replaced the blue tube from this. I also removed and cleaned the glass to clear the fungus build up on this tube and the green one but that's another story.

Re installed the projector, powered it up, and it ran beautifully ... for a day or so, then a lot of zapping noises and the unit died (I wished I could have turned it off quicker)!

I then changed all the ht components thinking that there must be a problem in this area and replaced the power supply board with a spare in unknown condition. Now the unit powers to 'stand by' without problem but try to power up and it runs for about a second, maybe two before cutting out. All three fans start to turn before stopping. The symptoms are the same using this board in my second unit so I suspect a power supply problem on the board. It sounds to be starting normally, just cuts out almost immediately.

I'm hopeless with electronics so any ideas as to what the likely cause of the problem could be would be gratefully received...

Hi Curt,

Many thanks for your reply which was much what I expected. I realize my old Sony is virtually worthless, but it is here sitting in front of me on my bench alongside another spares machine (a 1044QM with glass HACC/HD 6 lenses which I read are better than the 1001 TACs) ) and I don't have the heart give up on it without a fight!

I have given the FA power supply boards (the ones with the voltage change over switch ) to an electronics expert friend to test and if these prove OK, I'll start swapping boards one by one that I have now removed from the 1044QM. If I'm still unsuccessful, at that point I'll give up.

A shame I'm so geographically distant ... otherwise I'd come straight to you for a replacement CRT!! I have found a Barco 800 graphics locally. Would this be a worthy replacement?

Thanks again,

Hi Curt, Thanks again for your suggestions. I tried swapping the tubes and firing up the 1044. Nothing at all with the power supply board on that one but with the power supply board from the 1001, the two second cut off syndrome was identical on that unit too, which is why I suspect the power supply board. I hope to collect that today. If no faults were found I'll put it back in the 1001 which I have rebuilt again in anticipation. The 1044 has now been completely stripped so I have a full set of boards ready to swap one by one. Of course I could have two boards with an identical fault which would be just my luck. I'm afraid I have no idea which is the H deflection board or the convergence boards so I'll start with the ones with the biggest bits on them which are the PA board, the E board, the BA board and finally the large D board. I have already tried changing the big caged regulator unit which seems to make no difference. If none of this works, I will then have some beautifully clean and bright tubes and a set of HACC lenses looking for a good home. It will be the end of the story as far as I'm concerned as I need to get my life back! I'll let you know how I get on ...