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Discussion Starter · #1 ·
Hello Everyone, I got my first CRT projector, BarcoGraphics 800, about two weeks ago. I had a great time with it, but now it's slowing dying. Please help.


Short explanation:

The focus goes in and out of focus every half a second. Only the green tube is affected the most. The red tube seems to work fine and it's hard to tell with blue tube. Any advice?


Long explanation:

Three days ago while watching a DVD movie on S-video input 2, Barco lost signal. I press 2 on the remote and everything was normal.


Two days ago, the pictures looked soft and fuzzy, but I couldn't tell why.


Yesterday, Barco lost signal again. I press buttons on wired-remote, but nothing happened. I was really worried. I turned off the machine, pulled out every board to smell for any signs of burn and put everything back in. One of the connector seemed to be somewhat loose. Power back on the machine, everything worked fine.


Today, I finally find out what was wrong. The focus would go in and out of sync every half a second. This was hardly noticeable while watching images, but it is very apparent when you are trying to read words like subtitles. After testing the problem using individual colors, the green color gets affected the most. The red seems unaffected. It's hard to tell with blue. Also, this focus problems starts about 5 minutes after the machine warms-up. It looks fine for the first 5 minutes.


Any advice is greatly appreciated


Sean


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Things I have done to Barco that shouldn't have affected the focus.

1. Replaced defective Input-Switching Board

2. Used generic AC power cord, not the original

3. Spliced the wired-remote to make it longer. It really helps when you have to look into the tubes to make changes.

4. Used the machine 5 hours a day straight for two weeks.

5. Could not get the raster inside the phosphor area.

6. Maxed out screen size by corners of image almost touching the edge of forbidden area

7. Left the top cover off. Looked cooler.

8. Did not touch G2, astig. or any other mechanical stuff except for center and corner focus and aligning the crosshair for red and blue tubes.
 

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You need a new focus block/board. I am out, but am getting more in within 2 weeks.


Curt
 

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Discussion Starter · #3 ·
Thanks Curt,


A short definite answer coming from Curt is all I need to know. No need to second guess. But, I would like to try what my previous owner has suggested. He told me the focus block/board is on the far right side(looking from the rear) with the 3 red wires coming out the top. He said maybe I should try to adjust the 6 adjustment knobs on the side. Mainly the green one. What are these knobs do and how does upper knobs and lower knobs differ? I would like to know if it's okay to touch this and what they do before I mess with the controls.


Also, what can I do or not do to make sure that I won't fry the focus block again?


Thanks again
 

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Discussion Starter · #4 ·
Well, since no one had anything to say for 4 days, so I went ahead and turned the upper green knob slightly. I was told not to touch this because this was factory set and that I could fry the whole projector. When I turned this knob back and forth, the color green changed focus in and out. The funny thing was, even after 5 minutes nothing happened, meaning everything was working normal. Even after two hours of watching a movie, nothing happened. Yesterday, I let the projector run for 5 hours, and still everything was working fine. Actually, it looked better than before. I could even see characters at 1024x768 computer resolution with absolute clarity. I still don't know what these knobs are for, but for now, my Barco is behaving very nicely. If something happens later, I'll post it here, so that someone having a similar problem could benefit from it.
 

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The three top knobs are the electronic focus as you found out, NO harm in adjusting those.


The bottom three knobs are the G2 ort master brightness controls.


teh non-technical way to adjust these (my own invention)


1) Set brightness and contrast to about 60-65, turn the color control to 0

2) Go into the 'color balance' menu and set the color balance to 6500 K

3) Adjust the three G2 controls for a good B/W picture, not too bright, not too dim.


Oh yeah, use the video or S-video inputs for this, not the RGB.


Also, that fluctuation can be caused by a loose red wire going into that focus block, a loose CRT socket (not likely) or maybe some dirt got into the focus control ad you cleared it when you rotated it.


Curt
 
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