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Discussion Starter · #1 ·
Everytime I turn on my XG750 the red convergence is always off ONLY in the vertical direction! The blue is off a little sometimes too, but not nearly the same as the red!


It will NOT stabilize after running for an hour! I have to always adjust static from 0,0 to at least 6 or 7 in the vertical direction and or raster centering is adjusted and vertical static left at zero and then after 20 mins or so, it has to go back to where I started for perfect convergence???!?


After things have settled in 2 hours later or so, convergence stays stable then...


And again, my rasters are close to perfectly centered and static is at zero for all guns!


Any ideas?? Do the STK's need replacing on this XG??


Thanks for any help,

Brad
 

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It's possible that the STK's need replacing, but I'd check a few things first.

Are all the CRT mounting screws tight? Are the magnetics snug? Check and clean the electrical connections on the C-drive. Check the C-drive itself for bad solder connections. If all else fails, you MAY try replacing the chips, and then use heatsink paste instead of the pink rubber thingy to get better thermal transfer to the chassis.


Marc
 

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I have the same problem with my XG135; when I turn it on, the red convergence is always off by a bit. But after 30 minutes of running, it moves back into convergence and stays there. Moreover, the picture shrinks by about 3" vertically (somewhat less horizontally) during this warmup period. The black level adjustment also is way out of whack when I turn the projector on, though it stabilizes much faster (after about 10 minutes of warmup).


I've grown accustomed to this behavior as normal for this unit and just plan ahead accordingly - if I know I want to watch something at 8:00 p.m., I just turn the projector on at 7:30 and let it warm up. By the way, the XG also has an internal timer function that you can set so that it will turn itself on at a set time. Might try this if you want a nice warm projector waiting for you when you get home . . .


I'm sure this behavior has something to do with the temperature of the components on the convergence or deflection boards, but the projector otherwise is rock solid and has such a terrific picture that I'm loathe to poke around any. But the XG is clearly not as stable at turn-on as my previous 6PG Xtra.


John C.
 

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These sound more like convergence problems created by temp changes.

John, yours doesn't sound like a problem, most pj's take a half hour warm up to come into convergence.

Brad, can you discribe to environment your pj is in? Is it a small room, is it enclosed? Ceiling or floor mount, any other heat producing gear in the room, etc?
 

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Discussion Starter · #5 ·
Hi guys!


Thanks for responding...


Marc,


I will check and clean all conections and check all of the magnetics to make sure they are tight...


The thing with this projector is that it has low hours (just over 2000) and convergence correction is minimal, imo...and the projector is pretty much spotless inside and out..


Yes, I am still burning in this new set of tubes and they have just a shade under 40 hours on them...Could this have something to do with drift as well?? With the old tubes, as I recall, the convergence did not drift like this! So maybe it does have something to do with the magnetics?


I had the projector on last night for a good 4 to 5 hours and convergence is definitely not the most stable and the red likes to drift vertically a lot!...The PG9200 I have is pretty much dead on right from the start and stays that way no matter how long the projector is on for...!


KennyG,


The projector is table mounted in a fairly large room, and yes there is other gear that produces heat in the room...Heat has this BIG of an effect?? And again, the PG9200 I have does not drift like this at ALL and it was in the same room under the same conditions.


What I don't get is that I can turn the machine on, the red convergence is out in the vertical by up to 10 static clicks and it STAYS there until I make a change to static or raster centering...Then it seems that AFTER I make the changes to get everything lined up, it will then EVENTUALLY shift back to or close to where it was when I first turn the projector on!!?!


I will play with it some more and check all of the connections and fiddle some more with the magnetics!...Tonight I am going to turn it on and LEAVE it for 2 hours to see if it goes into place...


What the heck good is the projector if every time you turn it on you either have to wait for 2 hours before watching something or you have to adjust convergence while watching a movie?!?


Thanks for the suggestions...I will play again tonight! =)

Brad
 

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Hi guys,

The projector has a normal operating temperature and it cant be reached when you first turn it on, it has to warm up for 20-30 minutes for everything to come in, its stated in the manual to let it hit this before adjusting anything.


If you adjust it cold then it will drift out when its warmed up. This is perfectly normal.


The STK drive chips C and F run pretty hot, the reason for the warm up is to let the heat dissipate and stabilize trough-out the heat syncs XG series and bottom plate in the PG series. Yoke and tube heat up affects this also.


In a multi purpose application data and motion you have and use different signals most of the time. From the factory it comes dual purpose from video on up to the higher RGB signals and with different refresh rates so its not set up specific for a set freq that we usually use in HT.


You can get less 'cold to warm' drift doing the mechanical to the freq you are using but in any case do it only after the normal operating temp has been reached.


Drastic room temp changes like a a/c or heater vent near the projector can make it drift also and should be considered.


In a data application of text only you can see this 'come in' real time, still perfectly normal.


If you are doing a set up (mechanical) take your time and put the cover back on and take a look after it stabilizes and make the corrections before going to the remote, when you converge walk away from it and take a break every 10-15 minutes.


If your hiring this done by the hour give them the time to do this and allow for this extra time, its well worth it. Doug
 

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My XG1351lc appears to run hotter than my other 2, 6PG+ I have and is not as stable convergence wize. It ok after 1 hour running, is it because of the increased scanning frequency,s?
 

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Discussion Starter · #8 ·
Hi Doug,


Thanks for responding...


I did everything that you suggested...When I originally converged the projector, I let it run for at LEAST an hour BEFORE I made any adjustments at all!...And when I made adjustments, I would only do sessions for 10-15 minutes max like you suggest! I learned it from you my friend and a lot of other kind souls on this forum!


The thing is, the projector will NOT "come in" as you describe, even after running for an hour or more...I then adjust static for best convergence, and lo and behold, 30 minutes later it seems to want to drift back to where it was BEFORE I made the adjustments!


Brad
 

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Brad,

Check that auto data store is turned off in the settings menu.


If that isnt on then Id say you have a bad C drive, probably a cold solder joint at the STKs. Usually it will jump out or in and not drift.


It does sound like a thermal problem, you might try to reseat the drive into the vertical standing sub board (lens side) and check the ribbon connections at the rear of the board and at the mother board. Doug


Forgot:

Also try to swap the red with the green color connector (c drive) and see if it follows or stays at the red.
 
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