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Discussion Starter #1
I recently received a Hitachi 43fdx01b which works fairly well but has a dim picture. I have attempted to adjust the settings to brighten it, but it still does not seen right. I can probably take it to a repair shop, but as I try to do some things myself thought I would start here. I appreciate any help I can get.

-Marshallross
 

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A dim picture is a pretty vague description. Not much to go on...
 
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Discussion Starter #3
Sorry for appearing to come across as vague :daydream:

The tv takes about 30 seconds to have a picture appear at all and then when it does it is not very bright (kind of like me) but there do not appear to be any convergence issues. Everything looks clear and fairly sharp, just kind of "dim" or "filtered" maybe as if looking through sunglasses or "shades" if you are the cool type :joke: That's what I see at any rate, so I'm hoping that either that makes sense for someone "brighter" than me to have an idea as to the problem or someone to tell me to go get my cataracts removed (which at my age would be silly).

Thanks,

-Marshallross
 

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A good cleaning of the lenses and the mirror would be a good start.
 
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Discussion Starter #5
Thanks for the first step. I read somewhere else about a CRT rejuvenator. Is that the same thing as cleaning them, and if so is there anything special I should use?

Once I have done that and while I am inside of the unit, is there anything else you would recommend? Are there any controls that I can/should adjust that will allow the "guns" to be brighter? Do I need to consider replacing the bulbs?
I also read about cleaning the Spark Gaps on each CRT PWB.
# Remove the Cap, clean the contacts with thin fine sand paper then blow out excess.
# Reseal
This does not mean much to me yet, however maybe you know of this?
I appreciate the help and am willing to try just about anything that I can.

-Marshallross
 

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Thanks for the first step. I read somewhere else about a CRT rejuvenator. Is that the same thing as cleaning them, and if so is there anything special I should use?

Once I have done that and while I am inside of the unit, is there anything else you would recommend? Are there any controls that I can/should adjust that will allow the "guns" to be brighter? Do I need to consider replacing the bulbs?
I also read about cleaning the Spark Gaps on each CRT PWB.
# Remove the Cap, clean the contacts with thin fine sand paper then blow out excess.
# Reseal
This does not mean much to me yet, however maybe you know of this?
I appreciate the help and am willing to try just about anything that I can.

-Marshallross

NO! CRT rejuvenation is a last resort for aged CRTs and should only be done by someone who has a LOT of experience with it and only the best device for doing so. You need to start by doing a simple optical cleaning. While you are doing so, look at the phosphors to see how darkened the raster are might be. If it is really dark on all three CRTs, you simply will not get much more out of it because the CRTs are aged.

Evaluating this kind of problem may take more experience than you have. The degree to which the set is "dim" needs to be assessed with respect to other similar units. Your subjective impression does not communicate well via text. You might want to post an image.

Cleaning spark gaps has nothing to do with this problem. Only do so if you have a specific problem related to that.

The bottom line is, do NOTHING until you understand the problem better and understand exactly what you are attempting and why.
 
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Discussion Starter #7
I greatly appreciate your candor! I need to figure out how to get into it and do the cleaning. I want to "look at the phosphors to see how darkened the raster are", however, as you have noted, I am not well versed in this (not yet, but I am learning). Can you please give me a little more info on where I am to look for them? Once I clean them and check the above, I will take a picture of the unit after "warm-up" and post it (am I allowed to do that as a new member?).

Thanks again,

-Marshallross
 

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Take off the screen, remove the lenses, and clean the front of the CRT, the lenses, and the mirror carefully. Looking at the face of the tube observe whether the phosphors are darkened in the area that is scanned. You will see a distinct difference between the fresh phosphor around the edges and the used area. If it is very dark, that means that the output will be lower and nothing can be done. You can gain some emission in some tubes with restoration, but this is tricky and does not overcome aged phosphors.
 
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Discussion Starter #9
I removed the back and cleaned the mirror and the CRT lenses. I did not remove anything to better view the phosphors (if that is what I needed to do) as I did not want to change the alignment or discharge the capacitors accidentally. I put it back together and turned the set on, the picture was slightly better/brighter than before cleaning. I do not believe it is up to snuff yet, so I will attempt to attach some pictures next.
 

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Looks like soft worn CRTs. Look at the phosphors. You also need to clean behind the lenses. You revove them by taking out the four screws on the tabs of the lenses. Do not remove anything else and you will not have to do any alignment. You will not be subjesct to any discharge from the face of the CRT. You likely need to adjust both mechanical and electrostatic focus.
 
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Discussion Starter #12 (Edited)
OK, I can do that now that I am more sure nothing too extreme will happen. BTW, as I am not familiar with what good phosphors do look like, are there pictures somewhere I can view for comparison? As far as needing to "adjust both mechanical and electrostatic focus", I have a PDF copy of the Service Manual so I suppose directions will be in there. The clarity or sharpness of the picture seen ok to me, but I have been watching a 32" Toshiba Cinema Series for 15 years. I will post more results when I have gotten that far.

"Nothing is in the understanding that was not earlier in the senses." - kinda like that!


"The situation is now changing."
 
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Discussion Starter #13
Here are images taken as I removed the lenses and cleaned them and the tops of the CRT's. I looked at what I believe to be the phosphors to see how darkened the rasters are might be, but I am just not sure how good one's should look vs. darkened ones. I use a flashlight to look into the CRT's and view the phosphors, right?

If you look at the images I uploaded, can you get an idea or do I need to get closer? The set was turned off, so they look "bright" due to the flash on the camera.

As far as adjusting both mechanical and electrostatic focus once I am ready to replace the lenses, that is another area I am unsure of as the set's picture seemed sharp and clear but not very bright. Hopefully when we put it back together it will be brighter as long as the phosphors/rasters are ok, right?

Thanks again for all of your help. I will await your response and directions.

BTW, I too am a member of AVS Forum like you (for a couple of years now).
 

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Your phosphors are clean. For mechanical focus you use the set screws on the lenses, and for electrostatic you use the focus knobs on the black box that also has the screen controls behind the front panel.
 
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Discussion Starter #15
I think that there must be something more I can do as the picture is still not bright enough. I have used my Service Manual and have "upped" the levels on the controls inside the front panel of the TV. I have done some more reading and noted that there are those who advocate replacing the CRT Coolant. Looking at the picture of my Blue tube (maybe the Green as well), does it appear that it is cloudy? What do you think of this procedure?
 

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NO! Do not replace coolant if there is not a problem with it. I looks clear to me, and this is almost never a problem with Hitachi sets. It could be that you just expect more than the set can deliver. Without seeing it or making some measurements, it is hard to assess how bright it is.
 
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Discussion Starter #17
So what is my next step if it still is not bright enough to use in a normally lighted room? Also, the Blue does appear to be washed-out and will not adjust even with the inside front panel. This may be the cause of it not appearing to be bright enough, no?
 

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What do you mean by washed out and what adjustment exactly does not work. I am sorry, but it is impossible to tell you what to do without specific information. It may not be possible even with specific info. Post an image that demonstrates the problem and explain what it is that you are trying to adjust.
 
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Discussion Starter #19
Iacillo,
I recently repaired a 43FDX01B set, is there any way to set the grayscale without measuring equipment? I am going to do a DCAM convergence this weekend and was wondering if there were any other tweaks I could do to improve the picture, Granted the picture is not bad. Look forward to hearing from you.
 

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Buy a lamp that is reated for 6500K with as high a CRI as possible, or use daylight, to illuminate a gray scale card or gray reference card. Then visually match the gray scale setup on your set to the reference gray. Not an easy chore if you are not familiar with such settings, but if you have any gross gray scale errors you can likely correct them to some degree.

The IdealLume products are likely the best you will find and can be used for bias lighting when you are done using them for gray scale.
 
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