CurtPalme.com Home Theater Forum

[DGINSD]

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I got my Panasonic PT47WX49E up running, tuned up and dialed in nicely with a few minor exceptions that have some questions about.

First is the color decoder options in the service menu R-Y_A which is listed as the yellow tint adjust when changed to 00 balances out the red in the yellow and eliminates the orange cast that that the factory setting has so that one was rather easy to figure out. Where I'm having trouble is with the B-Y_G decoder adjustment, which is listed as the magenta tint adjustment. It’s kind of unclear to me where to best set this to get accurate color decoding. If all but the blue CRTs are turned off with a color bar pattern and then the B-Y_G is adjusted, it appears that it changes the level of blue in both magenta and blue, where as the R-Y_A adjusts the balance between red and yellow making it very easy to set properly with only the red CRT running. Can anyone tell me what the proper setting for B-Y_G is to get accurate color decoding?

I've found instructions on how to set the beam astigmatism, 2 and 4 pole magnets, the problem is this TV seems to be somewhat of a oddity, making those instructions near impossible to follow. From the CRT drive board going up the CRT necks the first rings that are supposed to be the 2 pole magnets do absolutely nothing, the service manual calls these the "alignment magnets". The rings that are supposed to be the 4 poles seem to be right and adjust the beam roundness. This set also has a third set which should be 6 pole these seem to move the dot pattern all over, left right up down, the service manual calls these "6-pole magnet (Dummy ring)". From what the SM says it almost seems like during assembly they installed the SVM assembly up side down, on all 3 CRT's, or installed the tabbed magnet rings in the wrong order on the assembly. Is this possible? The service manual for this set is only a partial manual, the rest of the manual Panasonic has you refer to a manual from an older set, I guess because what wasn't included in the manual for this set is the same as the older set they have you refer to.

Another issue I have is the convergence has a small amount of drift, not a lot just enough to need adjustment for perfect convergence. I've noticed that if I turn off the digital convergence to adjust the H-DEF and V-DEF settings it looks as if the TV was never set up properly i.e. corner, pincushion, trapezoid correction was never done, rather whoever did the initial set up went straight to digital convergence. Here’s my question is this causing undue stress on the newly replaced IC's, should I do a complete set up from scratch? This could be quit time consuming and a big project so if it’s not going to hurt the IC's, and it won't correct the convergence drift, I'd prefer to not get into it.

I've read on another site that this TV set has a designer menu; however the site doesn't tell you how to access it. There is suppose to be some edge enhancement settings that work in conjunction with scan velocity modulator that should be turned off when the SVM coil is disconnected. How can you access this menu and a list of parameters would be fantastic, hopefully you can unlock all the 480p & 1080i service menu controls.

Does this set have any controls that can correct gamma? This set seems to come out of black very slow, if I make video black output no light you can't see the pluge bars above video black in that test pattern. Maybe something in the designer menu that’s not in the regular service menu?

Lastly the screen variable resistors, the service manual states to adjust them by viewing the tubes directly with an all black pattern and adjust for minimum noise level in the green raster and match the others to it. This is the strangest method I've ever seen in a manual to adjust the screen VR's especially since the service menu contains no green cuts and drives so the balance between all the CRT's has a huge effect on the grey scale. Mitsubishi has you measure the cathode voltage at a test point, which seems like the most accurate way to me. Does anyone have a more accurate way to adjust these?

If anyone can help out with any of these issues, I would really appreciate it. I’ve asked around on a few other forums with no luck. I’m especially concerned with the astigmatism magnets and how these need to be set, being as they don’t seem to react as they should. I get some major flaring of the convergence grid on the left side of the screen, mostly blue and green, and I think these may be related. But if anyone has any input on any of these problems I'd love to hear it.

[macgyver655]

Well your post is just to much for me to read right now so I just picked out a few things to answer and you can re-ask in a shorter method anything I missed.

To adjust the screen controls i find the easiest is to go to a video input with nothing connected and turn off the blue screen if its on. Set brightness to about 50 or 60 and contrast about 70. Then look into each color lens and adjust the screen so the raster just disappears. I usually double check by raising the brightness and see if all 3 rasters appear and disappear at the same time.

As far as the convergence drift it could be from one setting being high to compensate for another setting being off so the answer is yes, I would neutral settings and start over. And yes it is time consuming. And yes, this would need to be done for different resolutions.

Do you have the service manual to follow for settings?

[DGINSD]

Thanks for the tip on incorporating the brightness control into the screen VR adjustment. It still seems like adjusting cor equal Cathode voltage on an all black raster would be more accurate, but I don't know what test point that would be.

Any thoughts on the astigmatism adjustments and what going on there (3rd paragraph). Why do the ring not coincide with what the service manual lists them as?

Also with the color decoder adjustments, the service manual gives a factory setting for both adjustments, but the one given for R-Y_A was not the proper level, so I would assume that the one given for B-Y_G in inaccurate as well. I don't have a meter, so I can't adjust that way, but I am able to shut off each gun to do it that way. Problem is B-Y_G adjusts intensity of both blue and magenta, so how to adjust?

[DGINSD]

I took a further look at the astigmatism adjustments on the CRT necks, and upon further inspection I noticed some markings on the tabbed rings. Starting from the CRT drive board moving up the neck, the first set of rings has a 6 on the longer tab, this first set of rings is also a different color than the others it's a dark purple. The next set of rings is grey in color and has a 4 on the longer tab. The next and upper most tab is also grey and has a D on the longer tab. The 4 and 6 on the rings would seem to indicate 4 and 6 pole magnets, the D I have no clue, according to the service manual this would indicate that the magnets were either put on the SVM assembly in the wrong order or the SVM was installed up side down. My question is would this effect how the magnets worked, the 4 poles adjust roundness but they are in the right position regardless, the ones marked with 6 do nothing, the ones marked with D seem to be the alignment magnets, would the alignment magnets being after the 4 pole magnets cause a problem in the way they operate.

The reason this bothers me so much is on the convergence grid the blue and green lines on the left side of the screen seem to widen and lose focus and I suspect this may be the cause, the red lines are fine everywhere. The only visible problem this causes while watching video is, high contrast, i.e. white next to black, I get blue overshoot in the black areas. Am I looking in the right area to fix this problem or is there something I've overlooked. Optical focus is good, so is electronic focus, the astigmatism/alignment magnets are the only thing I'm unsure of.