Anyone experience with repairing LCD projectors?

A friend from my degree course heard that I was building an LCD projector and was kind enough to offer me a broken 3M 8630 SVGA LCD projector, with the idea that i could maybe salvage it for parts. Of course, I didnt think twice about taking up the offer!

So, I now have this lump of a projector and have attempted to debug it. I have determined that the main transformer is function ing, providing all the different voltages required. Also, I have tried the 250W MH bulb in another projector and it works fine. The current symptoms are:

-No sign of life in the projector
-Not even the main fan starts up
-Maybe this means nothing, but there is a fuse on one of the modular PCBs that seems to 'fizzle'. That is, a small arc is observed between the fuse and its holder (it is intermittant, prompted by wobbling the board a bit). Maybe this implies something to someone out there with a bit more knowledge :)

If anyone has any suggestions for fault finding/repair then they would be graciously received. Even if I can't get it working, those RGB lcds look mighty handy :D




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I'm not a video projecto expert of any kind, but if the sucker doesn't power up, it must be a problem with the PSU.

If I were you (lucky bastard, I second that :D) I whould power it up and trace with a AC volt meter in the 1000V to see if the juice reaches the trafo.

If so check after the rectificator (might not be a bridge, I'm affraid) for DC.

In that kind of devices the voltage regulator is made often by semiconductors. See if you can spot some over heated stuff and If they are cooked OR THEIR SOLDER CONTACTS cracked.

I repaired a broken digital camera PSU by just resoldering the contacts of a voltage regulator ( it had some minor cracks that i only could see with a magnifier)

Good Luck,

If you decide to trash the projector, feel free to donate it to me :D