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Discussion Starter · #1 ·
Well, I had a shadow mask opening blocked, and RCA agreed to send out a replacement tube. I was able to get my local ISF Calibrator, Siegfried Riedel of Bjorn's Home Theater in San Antonio to do both the replacement and calibration.


Unfortunately, the "new" tube was worse than the old -- it had 5 pixels blocked, of which we were able to clear 2. Because the out-spots on the new tube were much more obvious than the one spot on the old, we put the old tube back in.


Siegfried took the new tube with him when he left; he is going to pow-wow with the RCA guys to see what to do -- whether to get a third tube or see if they will replace the set. It may be I should leave well enough alone.


I posted pictures of the operation at http://home.austin.rr.com/doctorjoe/f38310.htm ; The page was created in MS Word, and is clunky and takes a long time to load. I'm an html beginner, so if anyone can do a better job, send me an email.


Hob, there are a bunch of pictures of the three fans; the two on the outside of the set are held in by clips and should take only a few minutes to replace.


One of the things I learned was how to disable scan velocity modulation; to do so you need to remove the back plastic cover on the TV set, and disconnect one plug in the electronics. It was VERY easy.


1)The only cables you need to disconnect from the rear before you start are the ones attached to the section with the DirecTV card. Remove the back of the unit. There are ~ 10 screws holding it on. It should slide off easily (if not, you missed a screw).


2)Looking from the back of the set: On the right side you will see an orange/brown wire pair on the electronics mounted to the gun stem of the tube. This pair is labled P5201. It is about 6" long. It is the only orange/brown pair there is. Both ends are plastic push-clips. Disconnect it from the gun electronics; leave it hanging.


3)Put the back of the set back on.


After he disabled SVM, the sharpness setting moved from one notch from zero to middle of scale.


Siegfried showed me the difference in Video Essentials, using the test screen with the circles and numbers -- the numbers were definitely sharper after he disabled it. The picture was already very good, but I think I was able to see more detail in backgrounds -- like the tapestry/fabrics in Harry Potter.


Before you post any questions, you might review this thread over on the Home Theater Spot; I might have already answered the question.



Later,


Joe
 

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Discussion Starter · #3 ·
The pictures should be there -- they may take a few minutes to load. Like I said -- I don't have a clue when it comes to webpages, it looks like have a lot to learn:



One thing I noticed is that the window size is critical: it seems that the arrows "scale" with the window but the images don't. I've never used Word to do HTML before and it doesn't look like it does a good job.


If you can't get it to work, drop me an email ([email protected]) and I'll send you the word doc (it is a big file, though).



Joe
 

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Thank for the mention Joe It looks like I in a wheelchair, can't move the heavy set across the floor. Back access could only be obtained, by moving the set out from against the wall, I got to think that one out. I have cut, copied, and mailed it, then I printed it for future use. I put the sheet in my owners manual in my file cabinet. Thanks Joe :)
 

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Sweet, I see the pics now. DrJoe, please let us know how this turns out. Thanks a bunch for the pics and the instructions on how to disable SVM.


Question: Why is he tapping the glass with a mallet? Does it release the shadow mask? I was told that if a shadow mask messes up, there's no fixing it.
 

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Discussion Starter · #6 ·
My original problem was garbage in the shadow mask:


In order to dissipate charge, the inside of the glass picture tube is coated with a conductive coating. Near the tube stem this is generally a metal; away from the stem it is a conductive graphite coating called "daq" (pronounced "dack"). This coating can flake away, and, if it is charged, can be attracted to and lodge in the shadowmask, effectively blocking the pixel.


The only way to clear the pixel is to strike it and knock the garbage out of the shadowmask opening.


My set had one such pixel blocked. You can't see it from viewing distance, but it is obvious from a foot or two away. Siegfried was unable to dislodge it, so RCA agreed to replace the tube.


The tube you see him banging on was the replacement tube -- it had FIVE pixels blocked; Siegfried was able to dislodge the garbage in two of them, leaving three blocked, one of which was much worse than the single blocked pixel on the first tube.


So we put the old tube back in. Now I am waiting to see what RCA says to do. I see three possibilities: 1)send me a third tube 2)send me a new set 3)do nothing. A new set worries because the electronics/geometry on my set are good.


I am told that many tube manufacturers have specs that don't require each pixel to be perfect -- that up to a few blocked pixels is considered acceptable. We'll see where this goes.


In truth, this is a cosmetic problem only -- it doesn't interfere with enjoyment of the set.



Joe
 

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Dr Joe should be knighted for providing this info! thanks a million.


i disabled svm and here are my initial impressions :


satellite through s-video doesn't look too much better, although there might be minimal improvements.


on component/progressive dvd - i noticed that the TV resolves more fine detail. this also brings film grain out a little bit more...i didn't tell my wife that i changed anything and she mentioned the dvd we were watching looked granier than before. but this is a good thing, right? we're seeing more of the actual fine detail. also, the grain wasn't consistent, so it was definitely source-related and not any "noise" from the tv. On cleaner, less "grainy" dvd's the picture was outstanding. I also think overall contrast has been improved (the "grainy" dvd i mentioned was Big Lebowski, and it wasn't in all scenes).


in HD, i also noticed more "grain" on film material but this was added with a boost in detail.


overall they were small improvements, leading me to believe the SVM in these sets is minimal at best, but getting rid of it is still a good idea and VERY easy to do.
 

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Hello!


Please forgive me for jumping very late into this thread...


> there are a bunch of pictures of the three fans;

> the two on the outside of the set are held in by clips

> and should take only a few minutes to replace.


Replace? Did you find something quieter to replace them with?


> Remove the back of the unit.

> There are ~ 10 screws holding it on. It should slide off easily

> (if not, you missed a screw).


Can the back be removed with the set in its normal, upright position?


Thanks!

Dave
 

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Discussion Starter · #9 ·
Quote:
Originally posted by dbuffington
Hello!


Please forgive me for jumping very late into this thread...


> there are a bunch of pictures of the three fans;

> the two on the outside of the set are held in by clips

> and should take only a few minutes to replace.


Replace? Did you find something quieter to replace them with?
No;


Hob had been concerned that the multiple fans were running 24/7, and were going to fail, causing him to lose his window on the world. I made the comments on fans for his benefit. I don't think the fans are noisy, (see the first picture on the link above -- the set is inside an entertainment center that deadens the sound) and I'm not concerned about them failing.

Quote:


> Remove the back of the unit.

> There are ~ 10 screws holding it on. It should slide off easily

> (if not, you missed a screw).


Can the back be removed with the set in its normal, upright position?
Yes, of course. See the second and third picture in the link I have above -- warning: I am a novice at web publishing and so it may load very slowly. For the arrows to line up you may have to maximize the browser window.


Just make SURE that you remove ALL of the screws from the back -- if you pull and it doesn't come off easy, you missed one.


FYI, repeated in another thread somewhere, the second tube replacement went perfectly.


Joe
 

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Thanks for all the excellent info! (BTW ... The images at your web site load quite nicely for me.)


After a few extremely pleasant days of F38310 ownership, the fans do bother me -- my set is in the open air with the back against a solid, flat wall -- but not nearly enough to dampen my enthusiasm for the set. On the other hand, if I can do someting simple do damp the sound, I'll give it a try.


Thanks again!

Dave
 
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