| Author |
Message |
audimushroom
Joined: 25 Jun 2007
Posts: 44
|
| Posted: Fri Mar 27, 2009 4:44 pm Post subject: barco 1208 , convergence problem |
|
|
Just working with Chris to setup the input into the PJ, this is fed from the Lumagen HDP , set for 960p 72hz, focus is great with scanlines and phosphor grain evident.
Convergence is done at that frequency and is saved to block 1 on the Barco, looks good
change source or switch to the internally generated pattern and then reselect source which syncs just fine back to block 1 but convergence is off, resetting PJ and scaler and even different input to scaler makes no difference.
Its not a large amount out of convergence so its saving most of it, but its out and should'nt be, it does not happen if an internal pattern is converged.
Pj fully warmed up of course.
Why is it not saving? Anyone had this on a barco? found the fix?
|
|
| Back to top |
|
 |
Elaine Benes
Joined: 25 Apr 2006
Posts: 1416
|
| Posted: Sat Mar 28, 2009 12:58 am Post subject: |
|
|
While I'm not sure this is your issue, I remember having similar convergence issues with a 1208s/2 I once had. A super sharp, really nice projector, but the convergence was terribly drifty. You'd get it set up perfectly, then the next time you switched it on it would look terrible again. The only solution I found was to really dig into the MECHANICS of setting up a Barco and make sure the thing was almost converged without using any electronic controls at all. Make sure you pay very close attention to getting the vertical sizes and positions of the raw, uncorrected rasters as perfect as possible, dead center on the tubefaces, then make sure you're getting the middle convergence pretty much dead on without any correction, and be sure your horizontal sizes are really carefully matched. This is all done AFTER you're dead certain your projector's physical orientation to the screen is pretty much dead on square and level, perpendicular and centered. I remember the 1208s/2 had a very good factory mount that allowed me to get the position down to within 1/32" of where it had to be to be perfectly placed.
I worked on that setup over 2 days, but when I was done, it didn't drift any more...
|
|
| Back to top |
|
|
bbfarmht
Joined: 27 May 2006
Posts: 1273
Location: Where the Mississippi runs east to west!!
|
| Posted: Sat Mar 28, 2009 1:25 am Post subject: |
|
|
One thing I have to add. Now that you have messed with the projector, go back and read the layout and setup tips !
You should have a better idea of what it all means since you have been in the projector.
_________________
Adam
"Any society that would give up a little liberty to gain a little security will deserve neither and lose both"
Benjamin Franklin
|
|
| Back to top |
|
|
audimushroom
Joined: 25 Jun 2007
Posts: 44
|
| Posted: Sat Mar 28, 2009 8:36 am Post subject: |
|
|
Thanks for the responses.
Execellent mechanical has already been done and checked
this shift in convergence does not require the PJ to cool down , its instant, get it perfect, change to say an internal patteren and then back to the source and thats it , its changed slightly, but this does not happen if an internal patteren is converged thats what I don't understand
|
|
| Back to top |
|
|
secstate
Joined: 20 Mar 2006
Posts: 720
|
| Posted: Sat Mar 28, 2009 3:17 pm Post subject: |
|
|
|
Is the convergence off only in one direction (i.e., shifts left or right or up and down)? Is it on just red or blue or both. I had a bad horizontal shift and focus board that would cause my red convergence to suddenly shift left. This would occur randomly while the projector was operating.
|
|
| Back to top |
|
|
audimushroom
Joined: 25 Jun 2007
Posts: 44
|
| Posted: Sat Mar 28, 2009 4:41 pm Post subject: |
|
|
| secstate wrote: | | Is the convergence off only in one direction (i.e., shifts left or right or up and down)? Is it on just red or blue or both. I had a bad horizontal shift and focus board that would cause my red convergence to suddenly shift left. This would occur randomly while the projector was operating. |
Ok the red shifts left only, it only happens after convergence is set, its stable until the memory block is changed or any reason to re-sync the PJ. I have swapped out the the board and it made no difference.
|
|
| Back to top |
|
|
audimushroom
Joined: 25 Jun 2007
Posts: 44
|
| Posted: Wed Apr 01, 2009 9:17 am Post subject: |
|
|
I have a further update on this and its probably no surprise to some..
My 1208 is a 1208/2 and I recently got hold of some spare parts which although I thought were from a 1208 I found were actually from a 1208s, After a problem with the resistor on the original focus board I swapped out both the horizontal and focus board thinking because they were lower hr and made later they would be better and seemed to work fine.
Well changing over the horizontal board only cured the shifting, although the sync is not right so I guess the Focus board needs swapping too.
So now I think even though the part numbers match this is not the easy swap first thought. It would appear that the boards from a 1208s even if identical part numbers may cause minor issues because they were optimised for the chassis they came out of..
|
|
| Back to top |
|
|
secstate
Joined: 20 Mar 2006
Posts: 720
|
| Posted: Wed Apr 01, 2009 6:48 pm Post subject: |
|
|
| audimushroom wrote: | | So now I think even though the part numbers match this is not the easy swap first thought. It would appear that the boards from a 1208s even if identical part numbers may cause minor issues because they were optimised for the chassis they came out of.. |
It is possible but I have swapped a lot of parts in Barco and the same number board has alwasy worked for me as long as it was a good board. I wonder if you other board was bad. I don't think my experience represents the mean experience but I have had several bad H-shift/focus boards over the years which is why I suggested it as an option earlier.
|
|
| Back to top |
|
|
Curt Palme
CRT Tech
Joined: 08 Mar 2006
Posts: 24396
Location: Langley, BC
TV/Projector: All of them!
|
| Posted: Wed Apr 01, 2009 6:56 pm Post subject: |
|
|
|
I am guessing that you have two memory blocks that are set up really close to each other, and maybe the set keeps jumping to the wrong one. DO a 'delete all blocks' and a 'set to midposition' and start over. See if that cures it.
|
|
| Back to top |
|
|
|
|
