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Discussion Starter · #1 ·
RE: Manuals, Lens Access, Focus.

Posted on Keoi.com but updated here and interested in comments.


Hitachi 65XWX20B Build date Oct, 2002 w DP27 Chassis


Should also apply to any XWX or TWX model.


This unit was bought to replace a 60-inch Toshiba that the power company killed with a power surge. Some idiot stole the copper ground from a temporary transformer and the Toshiba took 1000 volts or more. I don't normally buy the extended warranty but fortunately bought a 3-year via Sears. Amazingly enough, Sears gave us full credit for the original $2,000 purchase price, repeat purchase price, of the three-year-old Toshiba as their extended warranty covers power surges. Set before that was a Pioneer RP which I really liked even though it was analog pots for convergence.


Looked at them all, but the Hitachi's looked far better, almost a photographic picture. The XWX series uses the larger tubes, better lenses (supposedly), etc.


After we got it, I let it run for a couple weeks and decided that warranty or not, I could probably do better than Hitachi in setting up at least parts of the picture.


1.

To do anything inside the set you really need the service manual which are apparently not available for purchase anywhere, at least for the newer sets. They are however available at the Hitachi service site which is http://www.hitachiserviceusa.com/ To download the service manual, you need to down to get a password. This took a couple of days. Used my consulting company name without a problem.


Any one know how fussy Hitachi is in this respect if I was ordinary consumer w/o Federal Tax ID? Nice site with lots of service manuals as well as training materials, Powerpoint presentations, etc. Very well done. Downloaded about 40 megs of stuff including training manuals. Thank god for DSL!


2.

Checked lens focus, mirrors, etc. Picture was not as well focused as I though it could be. Tweaked RGB focus which was pretty much spot on except for the intentional blue 1-mm each side out of focus. Used the manual 117-point customer convergence to temporarily displace the blue and red at a center point to check focus. (While this seems a nice feature, the fact of the matter is these customer settings can not be saved and will be reset when the "Magic Focus" convergence is operated.) Decided to trade some white balance, which I had also done with the Toshiba and Pioneer, by fully focusing the blue and cutting back a touch on the green screen. Will do a better job by doing the official version which is turning down the screens all the way, and then collapsing the picture with the service switch, and then advancing the RGB screens until a faint line can just be seen on the CRT tubes. Has worked well on every set I have owned as a good first pass setup.


Since picture looked overdriven (somewhat blurred intense colors), I turned down RBG screens about 5 degrees rotation counter clockwise. Before touching the controls, I used whiteout to 'dot' the shaft-mounting so I could put it back. Surprisingly the pots were not marked with that white anti-turn stuff. Picture got a bit better.


Decided to check the lens focus which I had done also with the Pioneer and Toshiba, both of which had needed tweaked. Used same procedure I had used on these other sets.


Step 1: Take the screen off. Theory was simple. Practice was not. Service manual says to pull up on sides and remove.

Not really!!!!!!! The clips along the top must have been designed by an engineer trying to keep the access panel to a nuclear reactor core closed!!!!!!!


The screen is held by a T slip-over-and-down about the middle of each side. You should be able to pull up about 1/4-inch and pull the bottom out about an inch when the screen is disengaged from the T. Then it simply should have been able to be pushed up about 1/2-inch and removed. The problem is diagramed below:



b= Plastic bezel (frame) at top of screen

s= rear projection screen

m= metal clip fastened by screws to top of cabinet

w= wooden cabinet top

.= ignore these as they are just spacers to get the html layout!


bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbwwwwwwwwwwwwwwww

bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbwwwwwwwwwwwwwwww

bbbbbbbbbbbbbbbbbb.........bmmmmmmmmmmmm

bbbbbbbbbbbbbbbbbb.....m bm

bbbbbbb......................mbbm

bbbbbbb.....................mmmm

bsssss

ssssss

ssssss


The top of the screen bezel has a molded 'L' section that slips down into metal clips spread along the top. The center line of these clips along the top is about 5-inches and 16 inches in from each corner and about 4-inches either side of the center. You should also know that the "magic focus" convergence has little solar cell sensors mounted on L-brackets at the center and both ends of the top and bottom of the wooden cabinet and on the middle of each side. The wires and mounting are about 3/8-inch in from the face of the wood. At any rate the top of the screen would simply not release. It took me two hours of prying with two putty knives and screwdriver between them to get the top of the screen free. I learned the hard way years ago that if you need to pry on something like this, including wood moulding, the best thing to avoid damage is to work two putty knives in and then pry between the blades with a screwdriver. However, a smarter person might have given up!!!


If you have to do this, try to keep the knives horizontally more or less and do not go past vertical because of the "magic focus" sensors. AGAIN, YOU MUST PRY UP, NOT OUT, TO RELEASE THE BEZEL FROM THESE CABINET CLIPS!!!!! Needless to say, the first thing I did when I finally got the screen off was to bend open these clips about another 1/16-inch so that I never have to do this prying again.


Measured the screen and found that the rear of the screen was 4.7 cm from the face of the wood cabinet. Used the same setup I had used with the Toshiba and Pioneer. Works as follows.


Cut a two pieces of cardboard about 12-inches high and 10-inches deep.


Mark the cardboard at 4.7 cm in from the edge. Tape on the outsides

of the cabinet at the midpoint of each side of the screen with 4.7 cm

protruding by using 2-inch masking tape


String a fairly taunt piece of masking tape from the outside of the cardboard

and across the front of the mirror box to the cardboard on the other side.

Do this at the top and bottom of the projecting cardboard.


Cut a one-foot square of waxed paper and 'stretch' between fingers to

take out the curl. Mount this at the center of the screen using the

masking tape to hold in place. Do same on both the right and left ends

also.


The waxed paper is just translucent enough to be a good rear protection

screen.


Marked all three lenses and then loosened lockscrew and wingnut.

Put set in customer manual convergence and used pieces of dark

cloth to cover up two lenses at a time. ( Used to use aluminum foil

but there are a lot of circuit wiring here and there in the mirror box.

Cloth is safer.)


Green was fairly good but needed to be twisted out about 1/-16 inch in the slot.


Red and blue were both slightly off and needed to be rotated out by

about 1/8-inch in slot. 'Out' is counter clockwise.



This adjustment is pretty sensitive and you need to twist the lens back and forth to find the best point. Aim for the best focus at the screen center, particularly with the green.


A little dust on the lenses but not much. Mirror was in excellent condition.


Used a moist cotton square with Edmund Scientific lens cleaner on the lens surface. This is supposedly non-residue. But it really is not, you need to get all of it off. Learned from an expert that cotton fibers are much less abrasive than wood fibres! Use cotton pads for cleaning LCD monitor. You can get the 2-inch cotton squares at the drug store in the makeup area. Much safer on lenses as cotton fibers are, as said above, much softer than wood fibers. Hate to clean a mirror that way however! Bounty makes some fairly soft paper towels that I have used before also.


(I might add that the cleaner for my LCD monitor is 22 oz of distilled water with two drops of dishwashing detergent and one-teaspoon of "sudsy ammonia" that you can get at a supermarket. Procedure is to wet a cotton pad and lightly wipe the screen. Then use a cotton pad to remove fluid. Then wet another cotton pad with distilled water and lightly wipe screen again. Then use two or three pads to lightly dry off the screen. Has worked great! )
 

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Dick,


Thanks for the incredibly helpful information.


Apparently Hitachi couldn't have made the alignment process more difficult if it had tried.


Les
 

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Will an ISF tech do all of this? Is it worth it? Why would the blue be intentionally out of focus? Are there other minor things that can be done without getting into the set? I've been questioning the focus of my 65XWX; can't understand why some HD looks great/sharp/focused and some does not.


Thanks.
 

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Discussion Starter · #4 ·
There are two kinds of focus.


Mechanical which is the lens on top of the tube and the focus of the beam inside the tube. The lens focus should be spot on at the center of the screen (other opinions here??????). The beam focus should be spot on for the red and green (center) CRT.


The blue focus in the CRT is set slightly wider (intentionally slightly out of focus)so as to paint more phosphors to make the picture brighter overall. Hitachi SM says 1mm wider on each side. I think the reason for this is that the blue phosphor is not as inherently bright as the red or green phosphors. I suspect that sharpening the blue focus changes the white balance slightly (less blue). Has anyone actually measured this with a color meter?


If some things look sharp and others do not it is probably not the lens or CRT. I did notice a big difference in apparent focus after the red push correction in the http://www.avsforum.com/avs-vb/showt...hreadid=192667 thread in this forum. I think this is because the red was being over driven washing out the other components in face tones. Someone help me out here is this isn't a correct explanation.
 

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Grey scale, color decoder, and picture settings should be recalibrated after refocusing. That is why focusing is the first procedure in the service manual...and should be first when tweaking.
 

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Quote:
Originally posted by RichUF
Will an ISF tech do all of this? Is it worth it? Why would the blue be intentionally out of focus? Are there other minor things that can be done without getting into the set? I've been questioning the focus of my 65XWX; can't understand why some HD looks great/sharp/focused and some does not.


Thanks.
Alot of ISF techs will do it.


ALot others won't


Depends on who it is...


Someone like Coyotes, Cheezmo, MichaelTLV, Gregg Lowen, ect... probably knows how to do this correctly...


Others will set your greyscale and run....
 

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Hi Mike!

I aims to please ;)


BTW...82 degrees here today. Had to have the AC on in the car while driving around in the Valley of the Sun.

Got that driveway cleared yet?:D
 

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I'll take a beautiful 110 degree summer day in Arizona *ANY DAY* over a wet, cold winter in the northeast. Coyotes, I envy you (disgruntled former Phoenix resident of 11 years now living in NE PA and hating it).


At least I have my 57SWX20B, a boatload of DVDs, and my beautiful wife to get me through the arctic months... :D
 

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It's on all the license plates: You can't shovel heat!:D
 

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Mfusick - It's all relative. Air conditioning is a wonderful thing.


Man, I remember my buds and I mountain biking at South Mountain after work during the summer months. Three days a week we'd start at 5:30 or 6:00, ride from the Pima Canyon parking lot up to the Buena Vista overlook and back down. Sometimes we'd go all the way to Telegraph Pass, drop down to the Desert Classic and do the big loop. We'd have the place almost to ourselves. 110 was where we drew the line. Hotter than that and we drank beer instead. Ah, the good old days... :p
 

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Mfusick,


your 10-20 days between thoughts cracks me up. You just trying to bump up your post # or something? :)


P.S. It's 75 and sunny here today.
 

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I just did the mechanical focus on my 57TWX20B and although I've tried to find every bit of info on this procedure beforehand, what I found in actuallity was quite different as far as removing the screen.


For the 57TWX20B:


1. Remove the speaker grill to gain access to the two screws that hold each faux marble panel on.

2. Remove the two screws that hold the lower screen.

3. Remove the two trim panels directly to the left and right of the center control panel. Behind these panels will be four more screws that hold the screen down!

4. The screen will now lift straight up with almost no effort at all!


I guess there arent too many 57TWX20B's out there because I haven't seen this info anywhere. I fought with trying to lift the screen off for at least an hour before I started wondering what was up! :)
 

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Quote:
Originally posted by Slammin
I just did the mechanical focus on my 57TWX20B and although I've tried to find every bit of info on this procedure beforehand, what I found in actuallity was quite different as far as removing the screen.


For the 57TWX20B:


1. Remove the speaker grill to gain access to the two screws that hold each faux marble panel on.

2. Remove the two screws that hold the lower screen.

3. Remove the two trim panels directly to the left and right of the center control panel. Behind these panels will be four more screws that hold the screen down!

4. The screen will now lift straight up with almost no effort at all!


I guess there arent too many 57TWX20B's out there because I haven't seen this info anywhere. I fought with trying to lift the screen off for at least an hour before I started wondering what was up! :)
The TWX has a little different cabinet and screen so that's probably why...
 
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