Help with old projector?

[justme]

I got an old "boxlight 3000" off ebay (cheap) thinking that if nothing else it would be good for parts/ideas. When I sarted it up it worked but with some problems. The blue has stripes of erraticly non-displaying pixels that will sometimes display as the temperature changes. After a while it heats up enough that the blue does not display at all. These sound like what I've heard refered to as a cold solder joint. I did touch/jiggle the blue ribbon after it had gone out and it came back.

This is one of those that splits the light into three, goes through three lcds and combines the light again for display. I am pretty sure that they are actually monochrome lcds because there is a red, green or blue filter before each lcd in the light path.

I'm not sure if this is something a putz like me could repair but it has what appears to be some good ir and uv filters along with some good mirrors, prisims and other optics that could be used in buildimg my own.

Any ideas? I will post some pictures and do some more testing as soon as I find my apartment under all this ****.

Thanks

 

[justme]

Some Pics.....Please Help

Hi, I took some pictures and I hope someone has an idea of what is wrong, if I can fix it or should just rob this ****** for parts.

The next few photos will hopefully help anyone to help me.

these are examples of the problem, verticle lines from the blue lcd panel.

 

[justme]

another example

Here's an shot from TV (built in tuner).

 

[justme]

Blurry picture

In looking for any obvious problem I mis-aligned the prism/lcd block, just have to get in there and fix it I did it once already. With it like this it doesn't show the lines but what's the point in that? Contrary to my first post on this, the ribbon was just not connecting properly, once I got the connection correct all three panels were running.


Does any body have any idea of what the problem is.

Or should I just start figuring out how to use the light source and optics?

 

[Stocker]

sounds (looks) like you know what the problem is.. you fixed the connector and it worked and now you need to fix the optics... what's the problem?

 

[justme]

Vertical lines

Hi thanks for looking.

The problem is that there are vertical lines when it is focused properly. Take a glance at the first 2 shots and you can see what I mean. I don't know enough to fix it without help from someone with more knowledge about electronics or lcds.

 

[justme]

Going to use it for parts.

I've done some more testing swapped the connections around so the lcds were being run from different colors. It seems that there is either damage to the blue lcd or the part of the main board that controlls it. There's nothing I can do about these kinds of problems so I'm just going to set it aside untill I get the rest of the parts to build my own. I may put some of the parts up for sale after I'm sure of what I need.

 

[Arnold_the_cat]

similar problem

Hi, I think I have the same problem as you. I bought an Epson EMP 5100 from eBay and when i recieved it I found it worked but there were vertical lines all down the picture. I took the thing apart and I noticed that the prisms which combine the images from the three LCDs don't look aligned. The prism is made up of three triangular pieces in a square. I expected the prisms to be the same height but two rise above the others. Its difficult to describe but I should be able to get a photo of it soon. Anyway, if you're able to resolve the problem you had with your projector, could you let me know how you did it? Cheers.

 

[justme]

LCD not prisms

Hi, the problem with my projector was that one of the LCDs was defective. I isolated all of them and moved them around to different control/video connections and found that the one that was being used for the blue was damaged. If it were larger I might have tried to find a fault but knew that it was beyond me.

There was nothing wrong with the prisms. The way the final one is fixed in place is flakey; it just uses some kind of soft glue (I think) and pressure from the housing around it so a sharp jar can misalign it from the objective lens making a blurred projection.

If you can run the pj with the case open try disconnecting 2 of the LCDs from any input and blocking the light that would pass through the path they use with a small piece of cardboard or something like that. I used business cards. By having only one LCD getting input and light you should be able to see if just one of them has the lines. If you can move them to other inputs you can then see if it's the LCD or the control/video going to it that is messed up. You will have to clean everything in the light path after doing this because of all the dust and such that will accumulate.

I moved the defective LCD to the red position since I don't see red light that well. That way it was a lot less noticeable. Finding a replacement LCD is only affordable by buying a pj that uses the same ones but has some kind of problem so will go for cheap. In looking for replacements I found a couple places that had them but will not pay hundreds or more to replace a part on an old pj that cost me less that a hundred.

 

[Arnold_the_cat]

Thanks for your reply

Thanks for replying, I have thoroughly investigated the projector and I am sure that the prisms are damaged. I attempted to fix them but i was unable to budge them. They seem to be bonded together. I've spoken to epson about the problem and they quoted an extortionate amount of money to fix it. I have therefore decided to sell it as spares or repairs on ebay. I'm glad you got your projector working. Thanks again for the reply.

arnold_the_cat

 

[FINKFLOYD]

Hi, I have an epson emp - 5000 aquired from ebay, I have the same problems.

I have both green & red vertical lines (green stands out more) and is horrible to view, the green lines are to the right

Also The prism unit, has 2 smooth + seemingly perfectly aligned, and then the other 2 are higher, except the one on the right is slightler higher.

But I think these should be that way as it seems solid and non movable.

But then again, this projector has definately been dropped at some point, as theres a crack on a corner and scratches etc on the casing..

Is this like your 5100?

I've tried messing with the alignment screws, to no avail

I got hold of a service manual, and it dosent say much but to get into service mode, i dont think you can without some tool.

@ Projection lens unit
The alignment of the projection lens unit is applied (position and fixing torque) in our factory. If the alignment is modified, clear image will not be made, because of the pixel divergence.

@ Electrical corrections (Driver board)

Some parts in the mechanical section of the optical system require some mechanical adjustments mentioned above. In the control circuit (driver board), the output driver for the display signal is slightly different from the output driver of other device (Driver board) in individuality.
The mechanical section itself of the optical system (e.g. light valves) must be electrically corrected. Therefore to obtain the best
image, not only the mechanical adjustment but the electric correction is required.

For this reason some correction values are written to Flash ROM of the driver board on factory shipping. For matching the optical system and electrical system, the electric correction is necessary.

Consequently, the driver board and the optical block (consists of optical head / light guide unit) make one set. At the factory shipment, following correction data are stored in the Flash ROM on
the driver board according to the specified optical engine.

Gamma adjustment data
Flicker adjustment data
Ghost contrast adjustment data
Sub contrast adjustment data

For the writing correction values, an expensive, special device and also skillful engineer are necessary, therefore it can not adjust in the field.

Id love to fix this bloody thing, waste of money, but i think i'll try to build one with a OHP if this is not successful
Look forward to any correspondence