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Discussion Starter · #1 ·
I have a spare 6pg+ running on a bench with the lenses off.


Now I have noticed a few things I did not expect or don't understand or there may be something wrong - here goes


1 - when adjusting the focus pots looking at the tube face there does not seem to be any change - is the change so small it's hard to notice but with the lenses on very small movement would be magnified on the screen or is there something wrong ?


2 - with brightness at 100 and contrast at 10 the green and red raster is easily seen, but while there is a picture I can not see the raster around the edge on the blue tube - it all seems quite dark compared to the red/green tubes again is this right ?


3 - finally I am having great difficulty with the green setup, something I have asked for help on before. With everything at 0 or centered as required I find that the squares on the test patterns are not even , they are much larger on one side of the tube then the other - so I use linearity to even this up then linearity balance to equalize the size across the tube face. Now the problem I get is that the horizontal lines become a elongated "S" IE one end of the lines are going slightly up and the other end slightly down.


Now I have another 6pg+ bolted to the ceiling which does exactly the same thing. I put that down to not have everything square etc to the screen, but as I am looking directly at the tube faces on this machine - which removes the mechanical setup issues- I cannot understand this problem. I thought it might be caused by pushing the raster size too close to the tube edge but it's still the same after I have used amplitude to reduce the raster.


I have tried to use various combinations of linearity and balance but cannot remove these wavy lines.The only way I get straight horizontal lines is to have various size squares. Although I am working on green it's exactly the same on red and blue.


Why are the squares so unequal on the tube face in the first place as this is the start of this problem. One final bit of information, I have recently replaced all the STK chips, but it did it before this as well


Previously I have great help from forum members and I am hoping for the same again, thanks in advance
 

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You won't see much focus change on the tubes without the lenses. It is too subtle for your eyes to see at that small size.


The linearity is normal like that and has to be adjusted. It is not a flaw. I think you need to adjust the cursor phase to fix the "S" problem.


This is all in the install manual. All part of normal set-up adjustments.


Marc
 

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If you defocus electronically then put contrast to FULL you'll see how the twiddling of pot works but make sure you turn contrast back down fast after you have optimum focus on pots and electronics.


Blue G2 sounds like it is not right. This is not something to play with unless you are feeling brave or have service manuals.


Gordon
 

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I do have a rough procedure for the G2's on the PG chassis. This does NOT work for the PG Extra.


Set the brightness to 60 and contrast to 75 and store those settings. Then hit the kelvin button. Does that fix the problem? Yes=hit store. End.

No=flip the normal/test switch on the video board to test. The switch is a tiny white switch on the left side facing the front of the projector next to the row of pots under the fan cover. Usually you can see it with a flashlight, and flip it with a stick or toothbrush handle.

Do the rasters show evenly? Yes=G2's are ok. Flip back to normal and manually adjust kelvin menu as below. No= adjust G2's to JUST make rasters appear when looking into the lens. Then flip the switch back to normal. Now hit kelvin again and adjust all the "B" value sliders for red, green, and blue to once again JUST make the rasters barely visible. Then adjust the "W" sliders in the menu to make the highlights white. You can use a greyscale pattern or black and white image for this. Aim for best greyscale using the "W" adjustments in the menu. Then store again, and return brightness and contrast to desired settings. This is a rough adjustment only, and should be used only if the projector is not working right to begin with. It is NOT a substitute for a proper base calibration, but it will give a watchable image. I always recomend having a proper setup done on the projector if the reference pots have been turned. NEVER turn the row of pots under the videoboard fan cover.

It takes special equipment and knowledge to re-calibrate these adjustments. You CAN damage the tubes!! So don't try this at home.


Marc
 

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Discussion Starter · #5 ·
WOW - Guys once again thanks for your valuable experience and help.


I played with pj again yesterday and this time I did see some change in the focus - I guess I was not looking close enough last time so I am happy that that is working OK.


I also concentrated on the wavy lines and played around with Phase a bit more. I have got it better than I have had before - still not perfect but I believe it's the best I have had so I am happy to bolt it to the ceiling and give that a go - I will do some more tweaking when it is up there.


I have also tried Marc's advice on setting the brightness and contrast and hitting the Kelvin button and Hey Presto ! the raster is visible - not as bright as red and green but it's there so I am happy to start resetting the astig and flare for each colour as this is definitely out on the blue, green looks OK and red slightly out. I will try doing this while it's on the table not the ceiling and with the lenses off it should be easier.


What I do find interesting is that it is obvious where the magnets for astig and flare were set from new because of silicone sealant - yet it is clearly out on the blue/red.


Once again this forum has proved why it's such a fantastic place to be - thanks for all your help.


Oh one more thing - it is becoming more obvious that I need to get the full service manual as I have 2 of these units both with great tubes, the idea at the price was that one would act as spares and I would get many years of pleasure from this superb unit. where, given that I am in the UK if that makes a difference would be the best place to get the manual ?


thanks once again
 

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If one was really picky about astigmation and flare you would notice that it changes ever so slightly from location to location and even upright to inverted. It is best done when it's in it's final location. Any wires, metal beams, joist hangers, even the ceiling mount that could emit stray magnetism will effect fine astig/flare adjustments.


Chip S.
 

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Yes, for the picky: The Earths magnetic field affects astig. It should be adjusted in the final mounting position.


Marc
 

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"I do have a rough procedure for the G2's on the PG chassis. This does NOT work for the PG Extra. "


Tinman,

Do you have a rough procedure for the PG extra or can explain the diferences in settings these G2's compared to the other PG models ?



Thanks,

Jim
 

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Discussion Starter · #9 ·
I understand the idea of magnetic fields etc and that the final tweak needs to happen in the pj's final position but -


I have played around with these adjustments for a while now having adjusted all astig electrical controls to "0" I find it impossible to get round dots across the face of the tube. Is it possible to acheive this or does everyone have to use the electronic adjustments to acheive as close as possible to this ? Should I be able to get good circular dots just by adjusting the 4 magnetic rings at the back of the tubes only ? My fear is if I do not get this bit right then when I put the lenses back on it will only magnify the issue and as the edges of the picture are usually the hardest area to converge I will only compound the problem. There are no other mechanical adjustments I am missing is there ?


If I have missed something obvious then I apologise but sometimes you can't see the wood from the trees and this is where the knowledgable people on this forum can drag you out of the woods so to speak.
 

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I recently adjusted one of the 6pgs and it should be done in the final place of projection and With the lenses On. You will need the lenses on to get the proper focus of each color. Use the manual in the steps it gives. It is not the easiest projector to adjust and takes some time. The getting of the halo on the dots perfectly round is done by the rings as you state. Don't be surprised if they aren't perfect. Just get them as best you can on the first time around. I went thru the settings 3 times on the one I was doing for a friend, and I see some slight shift after a month or so, and will be doing it again. I remember the manual I had was setup in the usual way but I noticed that the fine tuning of the convergence of each color ^v < > and in sections was almost missed in the turning of pages. It is really important in getting the edges right. I think the section was towards the back of the convergence section. Go slow and take your time and make sure it is really warmed up for over 1/2 hour. I tried to make the room quite dark and had to use a flashlight for reading the manual and the remote. You will need it pretty dark to get and see the fine tuning correctly. It will do a nice picture when set up. John
 

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When you do the mechanical astig/flare adjustments you should ONLY be looking at the dots in the center of the screen. The rest of the screen you have to correct with the electronic controls.
 

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Assuming you have electronic astig :(


None on my PG6000.
 

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It started on the PG+ model that the original poster states they have. That is the most welcome addition to the Plus models as it makes perfect dots across the screen pretty easy to achieve.
 

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Discussion Starter · #15 ·
gn2 and everyone else thanks for your help - you are right there are many posts on these subjects. I just wanted clarification on a few specific things asked in my own way and specific to my pj.


I have read many of them before and will read them again - thanks for the links guys
 

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Jim,

on the PGextra, the G2 adjustments are part of the reference white balance setup. The row of pots on the video board. If you touch those, it takes special tools and experience to reset the entire white balance reference. It takes 6 to 8 hours at times to get it exactly right, and that's if you know what you are doing. In your case I suggest you only use the kelvin adjustments to set your reference. Set the brightness to 60 and contrast to 75 and store those values. Now hit KELVIN, and set the Red, Green and Blue "B" sliders to JUST BARELY reveal the raster when looking into the lenses. Then set the "W" sliders to get good greyscale for the highlights. Store.

That will work fine, and if you have a color analyzer, you would use this menu to set the greyscale regardless.


Marc
 

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Hi Tinman,

I messed with those pots and everything is now fine :)


I AM KIDDING...


I learnt the hard way about those pots.


Then I learnt that to re-calibrate those pots you need one of the default video timings to get the correct voltage output (apart from the other tools).


But here is the fun part, when you do a eprom re-initialization you loose those video timings settings that you need for the video amp board calibration.


I kinda gulp when people are so quick to do an eprom re-initialization on the 6pg.


clopez
 

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Actually, even if you have the default video timings stored in the projector, without the actual source....

It won't work. You need the V-Dec board and a signal generator. And a scope, voltmeter, manual, and a lot of nerve.


Marc
 
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