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Discussion Starter #1
I recently went to redo the mechanical astigmatism on my Barco BG808. Red and green went very smoothly. But the blue was problematic. I could not get it to behave like the others did. When I went to adjust the 4-pole magnets with the cross paterns the blurring would never center over the horizontal and vertical crosses at the same time no matter how far around I rotated and adjusted the knob.


But what did happen is the blurring collapsed back down as if the tube came back in focus and I left it at this setting since with no others could I get the astig set. This does not seem correct. Leaving it like this I have to adjust the blue focus down to 18 versus say 49 for the red and green. There is no way to under adjust the focus though once you do this and get the flaring on either side of the crosses.


Anyone know what is going on here?


Brian
 

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Discussion Starter #2
Anyone?
 

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Thre are a couple of things that you can try.

You can move the CC magnets for and aft on the neck of the tube to see if you can find a better position for them.

You can move the electronic focus module as well to see if you can get better range.


Terry
 

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Brian

A little OT

I rem you from the Spot and Tosh ghosting.

I know you switched to Mits.

My question is

How do you like the Barco compared to the Mits? CRT FP is a tweakers dream IMO.

Steve
 

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Discussion Starter #5
Quote:
Thre are a couple of things that you can try.You can move the CC magnets for and aft on the neck of the tube to see if you can find a better position for them.

You can move the electronic focus module as well to see if you can get better range.


Terry
Thanks Terry. Anyone have pictures of these or know of a post discussing these adjustments?



Quote:
I rem you from the Spot and Tosh ghosting. I know you switched to Mits.

My question is

How do you like the Barco compared to the Mits?
Yep, still have the Mits too. But its deinterlacing sucks and I currently do not have a hi def box connected to it. I am waiting for the HDTivo. I really like the Barco and its 92-inch image is comparable to the 48 and some odd wide image of the Mits. Just slightly more washed out though due to size.


Brian
 

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Discussion Starter #6
Anyone got pictures or good descriptions for the adjustments terry described above?


Thanks, Brian
 

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Brian,


Sorry but my post has a mistype in it. The CC magnets should have been the CPC magnets which are the assemblies just in front of the neck board on the neck of the tube. The focus module is the next bid cylindrical thing forward. Both of these can be moved fore and aft a bit on the neck of the CRT.


Terry
 

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Discussion Starter #8
Thanks Terry that "seemed" to do the trick and was a fun exercise, despite all the scary looking wires and leads in there. A question though, obviously all these items must be set up when installing a tube. I have not seen any posts on the correct way to set these up? I could move one a certain way and another another way to counteract each other somewhat so I wonder what the procedure is for setting each up PROPERLY. Moving the focus module affected the astig, which in turn affects the focus. And the module affects the alignment of the grid slightly.


Brian
 

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Brian,

The procedure is move them till you can make a round tight dot pattern. It can get a little trickey and yours has some of the VDC from a few years ago that were quite tricky to set up. VDC in the past 6 months have really improved their guns which makes setting up the positions of this stuff easier.

General rule, put the electronic focus in the middle of it's range, and move the focus module fore and aft for best focus. Then bring in electronic focus for best focus, then work on the CPC magnets for best shaped dot. Then focus again.


Terry
 
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