Keohi HDTV - Brand Specific - Mitsubishi - Recovering from Service Menu Reset

[BRAND SPECIFIC][MITSUBISHI]

Recovering from Hitting Reset Button
In Service Menu

Tip from Mr Bob: A Mitsu 65903 owner, Doug McCoy, was tweaking his set when he did the "unthinkable": hit the reset button while in the service menu. As a consequence, everything was "screwed up" as he described it. The geometry, convergence, and colors were off."

Video specialist Mr Bob to the rescue. =)

"Well, it is done! It ALL looks spectacular now, just like a 65905 should. Just wish I could take all the credit ... Doug took what I had told y'all from the Mit tech, and went back exploring, but this time with a new respect for writing things down. He very carefully researched what would happen in each of the 2357 menus, and guess what? Several of them needed attention, and they ALL do something, it seems, despite only one or two being mentioned in the manual.

The first thing he remedied was the horrendous YC delay in the NTSC picture, and the skitterishness of the color, being scene-dependent as to whether it would appear or not.

What he found was that in the 3DYC menu, there was an entry called RDL, number 30, that had been set to 0. This was why it was so skitterish. When he played with it and reset it up a few numbers, it cooperated with restoring the color stability. I found that 6 gave me the best matchup in YC delay, using first the AVIA YC delay pattern, and then for more exacting results, the orange highlighted selections in the AVIA title menus themselves. When it's just right, the outlining disappears on whatever side -- right or left -- it was appearing on, and the orange is perfectly centered in the middle of the letter itself. You can tell this is a good YC delay phenom rather than a convergence phenom because the other selections, in white, remain perfectly converged while the orange highlighted headings go back and forth horizontally in response to the tweaking of the numbers in those YC locations.

Of course, Paul is the one who clued me in on where in general to do the fine-tune YC delay trimming, but the choices given us by Paul in the chroma section -- or was it the defl. jung. sec? -- are little steps compared to the massive steps available in the RDL settings.

The next thing he tackled was the lowering and misshapening of the image in the 4:3 graybarred NTSC section, where VPOS in the defl. jung. does nothing to help. Does nothing, period. The Mit tech told me he expected that, but did not tell me where to go to find a location that worked.

Doug found 2 locations that made a difference.

What he found was that in the PTC Logic section -- where the Mit tech had told us to look -- there is a location, number 25, titled Mode. It had been set to 3. Playing around with that one turned up 0 to be the correct setting. It recentered the image in the middle of the screen, up to down, and reshaped the picture quite nicely.

He also found that there are both VPOS and HPOS in this sector, both of which work! We had to go back and forth between VPOS and the modes before we got it totally straightened out -- actually all 3 had to be played with, ultimately -- but the end result was truly HD quality.

There you have it, folks. You now know more than the Mit tech does.

What's important to be aware of is that even though only one or two 2357 menus are mentioned in the Service Manual -- defl. jung. and chroma are the only ones, I believe -- all the menus there probably have massive effects on the picture. We found the ones that were critical to this particular op, but if Doug had screwed around even more than he did do, we'd probably have had even more work to do.

Which is a dangerous land mine on the one hand, and was our salvation on the other.

ALWAYS WRITE EVERYTHING DOWN BEFORE CHANGING ANYTHING! We can't stress this enough.

And if your remocon is trigger-happy, like one Sony I used earlier today, expect that every once in awhile you'll skip 2 registers while you were looking away, and thought you had skipped only one. If you are trying to play with this stuff by just remembering it, you may have just wound up altering some figure you never saw in the first place.

Or the Volume controls, which work the value numbers, are above or below the channel up and downs, which scroll the registers. You think you're de-escalating a value when you're really advancing a register because you were talking to the customer and/or answering a question, and suddenly you've gotten up and down mixed up just once. I've done it myself many times.

It takes a lot of concentration to do this job without writing things down, which you can do with certain registers -- grayscale NOT being one of them -- after you have become experienced; but due to land mines like trigger-happy remocons, even experienced calibrators have to be VERY careful, and concentrate to the max whenever working on a set like this. The amateur do-it-yourselfer working on his own unit who isn't concentrating very much in the first place, and is not writing down anything either, has a fool for a calibrator and an idiot for a client.

And from Doug's reaction when I quizzed him initially about having written things down like we've been saying here on these forums for years -- he looked like Trekkie Jon Lovitz when William Shatner asks him if he has been kissed yet, on that classic skit from Saturday Night Live where Shatner, speaking a Star Trek convention, tells them all to get a life, then has to backpedal really fast and figure out how to take it all back -- I think even Doug would agree with that appraisal of the situation now.

Of course for him that's now in the past -- his respect for how easily these sets can get screwed up from indiscriminate service menu surfing is now cast in stone...