Hi
I am having a problem with Horizontal Linearity on my 9500. To get the linearity right I have to run the C linearity at 12 ,which seems a bit excessive . It also causes a distortion in the grid . Any ideas what would cause this.
Thanks
Andrew

Hello

Send pix, it could indicate need to align magnetics.

Hi Tim
I don't think it is the magnetics I went through the magnetic alignment pretty carefully. The non linearity is common to all three tubes. I'll take pictures and post later tonight .
Thanks
Andrew

Is your projector positioning spot on relative to the screen?

Gino
Projector Is at right angles to screen.All measurements are dead on.
Here are some pics .Excuse the poor photography :o but you should be able to get the idea.
Thanks
Andrew

Gino
Projector Is at right angles to screen.All measurements are dead on.
Here are some pics .Excuse the poor photography :o but you should be able to get the idea.
Thanks
Andrew

When you're trying to show geometry problems, you should use green only. Especially since you claim to also have a distortion as well in the grid.

It's hard to tell what's going on from the posted images of the grids. And If I had to guess based on what I'm seeing. Your magnetics setup may need a little more attention.

If you want near perfect linearity, you'll have to spend a lot of time working with magnetic alignment to get the beam more precisely centered in the tube.

I've been repairing HDM's for years. And there can be a problem on an HDM with the linearity not being uniform. And if that's the case, it may need to be confirmed by proper testing on a machine that has the magnetics properly setup. To confirm that a problem truly exist, you should send that HDM to either Tim or Curt for evaluation.

And usually when the HDM fails to register the linearity properly, the grid would be distorted on one end of the tube or the other. And the lines would also be distorted or twisted to some degree. I'm not seeing that in your images. So it would be best to start all over from scratch, and show us the grid (green only), and show it right after zeroing out the green convergence, and show the grid without correction (don';t touch the linearity in the menu after initialization).

So it would be best to start all over from scratch, and show us the grid (green only), and show it right after zeroing out the green convergence, that's the first thing that came to mind when I saw that grid. Green convergence is not zero'd out during projector re-initialization or by re-setting the normal conv. menu's. probably a good place to start .

I swapped out the HDM and it did not make any difference. I will take a picture of the green crt only, with the convergence zeroed out and C linearity at mid position, tonight
Thanks
Andrew

Here are the pictures of green only ,convergence zeroed out.The C linearity problem exists across all three colours and is the same on each so I thought that would eliminate the magnetics setup.
Thanks
Andrew

Need the picture !!!

OOps! pictures didn't load .I'll try again

Measure the left top corner of the screen to the right hand side of the projector

Measure the right top corner of the screen to the left hand side of the PJ.

Pick an identical mirror image of left and right side of the screen........

To me you pj is tilted towards the left. the right screen to left pj will be longer if that is the case..............

You should aim to be mm perfect in the physical installation.

I checked the measurements again they are spot on. I had a G90 in the same spot a year ago and it did not have this problem. I can use the c lineariry to correct for this so I geuss I will live with it for a while and see if anything changes. :confused:
Thanks
Andrew

Is there even a problem running C Lin at 12?

I guess stability would be affected and more heat and stress on the convergence circuits. From the way the projector behaves I don't think this is a mechanical setup issue.The problem appears across all three tubes and even if I move the projector in relationship to the screen the problem remains the same.Also the problem stays if I vary the magnetic setup on the crts. The projector is an Ultra,but an early one that has the model # 9500HS .I also had some early problems where someone had modified the Vertical Deflection board.
http://www.avsforum.com/avs-vb/showthread.php?t=694984
I removed the small circuit board and repaired a couple of cut traces ,it works OK now.I thought maybe that the vertical board had something to do with this problem but from what I have read the signals for this a generated on the control module and then applied to the convergence circuits. Like I said before I'll just live with the problem and see what the long term results are . :D
Thanks
Andrew