CurtPalme.com Home Theater Forum

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

I am having problems with the Red convergence. I do a mechanical alignment to the green with the Red and Blue, and while doing a convergence, the very outer edges of the Red will not align with the Green and Blue. I hit the limit with the remote moving the horizontal bottom right and upper right on the Red. Mechanical alignment is right on top in the center rectangle. I reset all convergence settings and started from scratch from the service menu. Please give me your suggestions.

Thanks,

Mark Sad

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

You might start by telling what kind of projector you are using. It makes a big difference.

Only Marquees offer raster centering by adjustments to the focus yoke.

First things first, though: Basic mechanical centering. Zero out all convergence and geometry adjustments. Zero out the CPC rings, too.

In fact, UNPLUG the convergence and focus yokes. Center up the rasters in each CRT. Re-aim the red and blue CRT assemblies to match up to green right in the center of the image.

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

That is an important part of the overall alignment process. If there's a bias on the convergence or focus circuits, you'll see the picture snap toward the center when you unplug convergence or focus after you've already zeroed out their adjustments.

That bias can keep you from getting full use of convergence.

Just be really careful not to unplug a DEFLECTION coil while the machine is operating. That would be bad.

**Curt Palme** · Posted: Sun Apr 10, 2016 1:58 am Post subject:

Actually I've tried to spot burn a Marquee by unplugging the H and V yoke leads while running, and it refuses to do so!

Why did I do this? Because many years ago I installed a 9500 Ultra in edmonton, and shortly thereafter, the customer said that there were lines burned in the pix. I freaked, and tried duplicating the problem with a toasted tube set, and couldn't spot or line burn the tubes. He did have a power outage, so I took a risk, and drove back 12 hours 1 way to find that there was a tiny bit of banding that I didn't catch upon initial setup. My bad!

That aside... disconnect the astig and convergence connectors, and use the focus yoke movement to center the crosshatch in the middle of the set. There are two sections to the focus yoke, held together by 3 brass bolts and wingnuts, and a dab of glue. Loosen the wingnuts, (don't take them off!), and use an Xacto blade to loosen the yokes. A little movement moves the raster a whole lot, and make sure you're not overshooting the edges of the tubes. Once that's aligned in the middle, you can use the coils along the top edge of the HDM to narrow or widen the rasters to match on the extreme left and right sides as close as possible. Once that's all done, reset the tube magnet astig before connecting the astig connectors.

Obviously connect and disconnect all plugs while the set is off, and make sure you don't put the convergence board connectors 1 pin off, or you'll smoke the convergence board!

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4379 Location: Phoenix

Hello

Curt mentions matching red green and blue widths, you will also want to match heights in the service menu.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

No, when checking for possible bias issues with convergence or focus, you WANT the projector to be turned on and running.

This applies to astig, too.

If you don't SEE the difference when you remove or install the plug, you won't KNOW how much difference there is.

It's perfectly safe to disconnect or reconnect, focus, convergence, or astig while the projector is running. The only sacred plugs are the two DEFLECTION plugs per tube assembly. You don't want to mess with THOSE while the PJ is powered up.

My baseline alignment is to disconnect those three plugs (focus, astig, and convergence) and zero out the CPC adjustments, then adjust the (stock Thomson type) focus yoke to be mechancially centered so that the front and back half shells are aligned with each other on all sides. I would like to avoid shifting the focus yoke body laterally if it can be avoided, but that may be necessary.

I then use the 2 pole adjustment CPC ring to center the raster on the tube faces, using the all white raster screen.
Then I bring up the convergence grid and mechanically center the tubes on green.

There's usually a balancing act you have to perform when it comes to raster centering as this can be achieved with both the
shift feature of the focus yoke and the 2 pole centering function of the CPC rings. The best possible alignment may require you to adjust both of them. Your guide is the shape of the dots in the convergence patterns when you defocus the tubes electronically. You want the defocused pattern to be as circular as possible and evenly balanced on all sides.

The built-in guide in the Marquee (HELP button on the remote!) is good but it's only a guide, not a compete and comprehensive instruction manual on how to get a perfect setup. Your own judgement plays a big part in getting a perfect setup.
That sometimes involves going back and retouching a previous adjustment.

Pro tip: To get the linearity correct, find or draw your own simple corner-to-corner X pattern and display it. Only when linearity is set correctly will the diagonal lines all be straight lines. Any linearity problem will bend the lines. There is NO test pattern that is better for linearity adjustments than a simple X pattern that spans from corner to corner of the viewable area.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

After zeroing out the projector I pulled the astig and convergence plugs with a grid on screen. There was quite a bit of movement on the Red and Green when the convergence plugs were pulled from the board. There was no movement from pulling the Astig plugs. Should I be concerned that there is a problem with the convergence board. I'd say there is about a 1/2 inch of movement while plugging and unplugging the convergence leads. I've pulled the HDM, focus boards and checked for any bad caps on everything. None bulging or leaking.

Mark

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4379 Location: Phoenix

Say Mark

Movement is only a concern if the CENTER moves, that is done through the scan yokes. Get a 0.10" hex head plastic width coil tool and match the red and blue raster widths to green. And the heights.

Look at this: http://www.etechvideo.com/techtip9.htm

and scroll down, read everything below PIC 19

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4379 Location: Phoenix

Hello

That is not significant. Proceed with height and width matching.

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

Tim,

I redid the mechanical focus on the lenses with the leads unplugged. I still have about a 2 inch bow at the top and bottom Red right hand side relative to the Blue and Green. That being with the center grid overlapped on each color. Raster is centered on the tube face. I am concerned that the Red convergence will hit the limit electrically because it is so far away from the other 2 colored grids on the right hand side.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

That'll converge out easily. No problem.

Generally the amount of shift available in covergence is about 1 and 1/2 grid squares. You need about HALF a grid square's worth. No problem at all.

If you have the ACON system, use it to get started. It's cool to watch it in operation anyway.

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4379 Location: Phoenix

Hello

I have fully advised you how to fix this.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Tim's advice is highly reliable. Do as he says and you'll be in a good position to start the convergence process.

We have all those geometry controls to help fix what's not right.

Be sure you center up the linearity controls, too.

racerxnet · Joined: 20 Jun 2007 Posts: 362 Location: Illinois

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

Everything those guys said, except I don't like telling new people to pull plugs in a dark room. It's too easy to re-install one and have 1 pin off (3 on 3 vs. 4 on 4 ) , and you'll blow that convergence channel instantly on power up.

zeroing out convergence is easier, just push the number zero while in any convergence menu, and then again in the " service mode" to zero out green. centering the grids in the tube face by using the center square only(this is done with deflection and doesn't use the convergence circuit at all). Then pivoting tubes to line up edges of grids.
Look at grid sizes, all 6 edges should be very close. If any grid is too tall, adjust in service menu under RGB heights .

If any grid is too wide, adjust with special plastic tool (I have some here I usually send people with their board packages)

Once all 3 grids as as close to the same size as possible, converge green to square up to screen. You source must be on, you are converging one specific resolution at any given time. If you have multiple resolutions from different devices, you will need ot use channels to save a different recall memory for each one.

then finally do a fill interpolated converge for R & B to green. Follow up with a Guided or zone convergence to get it perfect.

You can go deeper than this of course by tweaking yokes but this is an easy and fool proof approach for beginners on the marquee chassis.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Have a flashlight in hand any time you are even thinking about sticking your hand into a running CRT projector.

If you do pull any plugs, use the light, put them on right, don't do it by feel.

I only pull plugs to set up the basic mechanical alignment. After that it's all done with all plugs connected and the related
function's settings at their zero or centered values until it's time to make those adjustments to that function. (Focus first, astig later.)