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Calibrating HD Decoder for 03/05 Series Sets

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Tip from Mr Bob:  "Please forgive me if this information is already out there, I haven't had time to surf the HD forums lately. If not, if this is new to you, please enjoy it. I just did another 73903, and it came time for redoing the color decoder in the HD mode to eliminate the dread red push, at the request of the customer. An extra, but usually considered well worth the extra fees.

This is doable in a fairly direct manner in the NTSC and/or 480p modes from the test patterns from your DVDP, as long as you have access to the correct Mit information discovered by Paul Carleton - see But how do you do it without a DVDP to throw up the correct patterns on the screen, those ingenious flashing ones laid onto AVIA by the incredibly intuitive Guy Kuo?

We looked in the service manual and found that the defaulted settings for the color decoder, out of the box from the factory, were the same for HD as they are for NTSC and 480p.

Therefore, they had been blindly programmed, filling the 2 areas identically already -- HD and 480p/NTSC -- and are standard for all HD Mitsubishis, at least the ones that manual covers. These are the ones that set your HDTV's color decoder for automatic red push.

You need to start, of course, with custom tailoring the patterns from your DVDP -- either progressive or NTSC, it doesn't matter -- to the correct settings to eliminate the red push, as all TVs are slightly different. (That said, Mit still has total success enforcing its red push bias on us all with exactly the same factory settings for every HDTV they produce, unless the newer ones are different, which I doubt.) But not having had the opportunity yet to compare the new settings I've come up with among several different units, I still believe in custom tailoring the anti-red push regimen to the TV involved, for now. If I find that all Mit RPTVs I calibrate consistently come up with identical settings for linearizing the factory-biased color decoder, I'll share those values on the boards. I believe Rodney Gallie will be sharing the values we came up with, directly, for his TV last night.

Then you take those new settings and transfer them over to the HD section, number for number.

The results can be verified with the red, green and blue escalating-intensity stripes of the color decoder test on AVIA. The results we came up with definitely eliminated the red push in NTSC, and our eyes told us the same thing for the HD, since there was really no totally accurate, native way to get the test patterns up there in HD. At first the red was way up there, the green was right in the middle, and the blue was down in the nether region. A heavily skewed angle downward, among the 3 stripes, going at about 45 degrees, from up in the left corner to down in the right corner.

Afterwards, all 3 stripes were basically at the same level, results showing a straight across line, or "curve", testifying to the newly-created linearity of the color decoder.

Viva Guy! Thanks for giving us the tools to defeat the arrogance of Mitsubishi on this one.

And thanks to Paul too. Nobody had figured this one out until he did, and Mit wasn't about to tell anybody.

Check his website out for even more improvements possible to do to the Mit units, at least the ones we haven't been newly frozen out of by Mit, like we have on the newest 07 units."