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Discussion Starter · #1 ·
I have a Marquee 9500 LC ULTRA.

In your opinion is it right to mount on its tobes the 2-4-6 pole magnet rings or is it ideal the original 2 pole magnet to adjust anly the flare?

Thanks
 

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I have found that with the older 2 pole rings 50% of the stig flares were triangular and not correctable.

If you can find a set at VDC, the 2-4-6 pole rings are the best. In conjunction with the Marque's electronic stig circuit, it allows for perfectly round stig dots corner to corner. It's a nice upgrade for less than $100.
 

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If I can ask a question regarding the magnets... does this improve the picture quality in any way at all?


I mean, there is lots of moving images that are on screen and I just wondered why this is relevant. After all , I'm pretty sure that no member is using his pj for CAD is he?, so no static images with lines all over the place. I'm only trying to convey my conception of 2-4-6 pole magnets and hope that someone could enlighten me and others as to how this helps during movie watching.



Just a dumb&%^ss trying to understand


Thanks

MG
 

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Discussion Starter · #4 ·
Thanks for your fast replay Dragamn.

I already have the 2-4-6 ple magnet mounted on each neck.

The problem is that in opinion of some people the Marquee configuration was born in order to the presence of the single 2 pole magnete ring.

The installation of the 2-4-6 can damage the regular functions of the electronic beam. You are right when you speak about the perfect geomestry of the electronic beam but the other dynamic adjustments could be damaged by the magnetic influence of the three magnet rings.

An example is the flare regulation. When you display the crosshatch pattern (contrast and brightness high and overfocus) and you want adjust the core so that it can become perfectly centered into its same ghost, you think to do the best thing. But when you go from underfocus to overfocus all the crossahatch pattern moves. It means that there is a problem and the perfect astig. and focus cannot be made.


Excuse me for my bad english.
 

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Quote:
Originally Posted by crt nuts /forum/post/13010257


If I can ask a question regarding the magnets... does this improve the picture quality in any way at all?Thanks

MG

well it's quite simple really. What your trying to is focus an electron beam, which is round. The idea is to make the beam as small and as round as possible. If you take a circle, and squeeze it into a triangle on 3 sides, it will make the points of the triangle form a larger footprint than the original circle. that's why perfectly round dots corner to corner will give the tightest focus.

Quote:
Originally Posted by cencio /forum/post/13010330


Thanks for your fast replay Dragamn.

I already have the 2-4-6 ple magnet mounted on each neck.

The problem is that in opinion of some people the Marquee configuration was born in order to the presence of the single 2 pole magnete ring. .

I have been on this forum for 5 years and never heard that opinion before. In fact the new 8500/9500's come standard with both 2-4-6 pole rings and dynamic stig and that seems to contradict the opinion that the 2 things are not compatible?


Quote:
Originally Posted by cencio /forum/post/13010330


The installation of the 2-4-6 can damage the regular functions of the electronic beam. You are right when you speak about the perfect geomestry of the electronic beam but the other dynamic adjustments could be damaged by the magnetic influence of the three magnet rings. An example is the flare regulation. When you display the crosshatch pattern (contrast and brightness high and overfocus) and you want adjust the core so that it can become perfectly centered into its same ghost, you think to do the best thing. But when you go from underfocus to overfocus all the crossahatch pattern moves. It means that there is a problem and the perfect astig. and focus cannot be made.

Excuse me for my bad english.

If ramping the focus up or down is causing the grid lines to move, it means something is not adjusted right. I don't think it's the fault of the 2-4-6 rings.

I would try this. with power off Unplug the 3 stig leads from the amplifer board on the rear panel. Go into both convergence menu's,including green, and zero them out. Then set your flare using the 2 pole ring (focus 0, contrast 80) . Now set focus to 100 and adjust stig using only the 4 and 6 pole rings, make sure you don't bump the flare ring. now bring up a cross-hatch pattern and see if ramping focus moves the pattern around. It should be stable.

Last thing is to power down and re-attach the stig leads. touch up the stig as required for perfect circles corner to corner. If the last step causes your raster to move with focus adjustment, then there migth be something wrong with the stig amp or focus coils. In reading VDC tech. bulletins, it says that exposing the f coils to any outside magnetic device ( like a magetized screwdriver ) can permanently alter their properties.
 

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Hello Draganm


A buddy of mine has an 8500 and when doing the stig flare there is an almost vast difference in the circle size on the left side of the screen compared to the rest. The circles on the left 1/4 of the screen are almost 1/5th the size of the circles (flared with dots in center) of the rest of the screen.

Can you tell us what the reason for this is?


Thanks

MG
 

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wow, that's really wierd, i've never see nanything like that before. IS it the same on all 3 tubes or?
 

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Yes and it is also not very easy to do the rgb focus on the left side either. It does not show on the pic as much as it does on text. Any ideas??
 

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well the first easy thing to do i verify that this is happening on the face of the CRT and not just on the screen, just to eliminate optical focus as an issue.

Since it's the same on all 3, I would suspect the focus board and try a different one. It sounds like you've lost EM focus control on 1 side of the screen.

This board is susceptible to damage from the normal static discharges that occur in CRT projectors. There is a fix for this on Curt's web-site that came from Christy Digital in 1998. This won't fix your old board in case it is bad but the fact that the bulletin exists is an indication of where to start.
 

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Discussion Starter · #10 ·
Thanks Dragamn!

These are the words that I would have to ear.

Because I was utterly convinced of your opinion and of the fact that the last Marquees born with the 2-4-6 pole magnet rings.

Apologyze me for my post but it was simple the real things that i have ear the last friday from a italian forum CRT expert.

Best Reagards
 

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I have a Marquee 9500 that I put 2-4-6 stig rings on at the same time I replaced the neck boards with MP modded versions. The tubes in my projector

are new re-built VDC tubes so I was trying to correct a triangular spot shape on the green tube, which it did help a little bit. Don't really know what helped more, the rings or the boards, but when I was finished setting the system back

to working order, my wife walked in the room and just said "WOW"! This says

a lot because she didn't really know what I was doing so she wasn't looking for the improvement. I recommend the 2-4-6 rings but I also recommend doing the neck boards too. In order to do the rings you have to take the back assemblies of the tubes off so you might as well...


Do not get re-built tubes. My bad!


Dave
 

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Dave,


I also have both green & blue re-built tubes on my 9501L. I can't get uniform white on whole screen. I have reddish color at the left of the screen but the tube faces looks good. What's your problem?


Cheung
 

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Cheung, try contrast modulation in the service menu to help with the uniformity
 

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Not sure if there was anyt method to E'home's madness with regards to magnets. I've had 8111+ sets in with 6 poles on all tubes, and have had more recent 9500s with only 2 poles on the tubes (!).
 

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I cant get a even uniformity on my 8500 i can get one side nice and white but the other is greenish. This was noticed more after a HD144 install. I dont think I have the contrast zone modulation version 4.1 is my software.


Athanasios
 

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I have a 9500lc that was made in 95. I assume if it has 2 adjustment knobs that means its a 2-pole stig magnet?


Yes I have noticed on the L,R, TOP and BOTTOM I could not get good circles while doing the stig adjustment in the service menu.
 

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Discussion Starter · #17 ·

Quote:
Originally Posted by draganm /forum/post/13011325


If ramping the focus up or down is causing the grid lines to move, it means something is not adjusted right. I don't think it's the fault of the 2-4-6 rings.

I would try this. with power off Unplug the 3 stig leads from the amplifer board on the rear panel. Go into both convergence menu's,including green, and zero them out. Then set your flare using the 2 pole ring (focus 0, contrast 80) . Now set focus to 100 and adjust stig using only the 4 and 6 pole rings, make sure you don't bump the flare ring. now bring up a cross-hatch pattern and see if ramping focus moves the pattern around. It should be stable.

Last thing is to power down and re-attach the stig leads. touch up the stig as required for perfect circles corner to corner. If the last step causes your raster to move with focus adjustment, then there migth be something wrong with the stig amp or focus coils. In reading VDC tech. bulletins, it says that exposing the f coils to any outside magnetic device ( like a magetized screwdriver ) can permanently alter their properties.

When i work with this procedure must I disconnect any source?

This has been always my great dilemma.

If I go to a complete adjustment from zero point and puttin all the values to 0 or 50, must I depart with the sources connected or not?

Thanks
 

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Hi Gino,


I checked the service manual but the contrast modulation is not installed. Do i have to install a modulation board and where should I install it? Thanks.


Cheung
 

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guys how do I identify which sting rings are in my projector. I ask because I have poor dot focus anywhere but the center. I will try and post a picture later.
 

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Quote:
Originally Posted by barcoguy /forum/post/13044218


guys how do I identify which sting rings are in my projector. I ask because I have poor dot focus anywhere but the center. I will try and post a picture later.

That is probably a bad focus board. Do the side focusing controls have ANY effect? If not, I'll bet the focus board is bad.
 
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