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Discussion Starter · #1 ·
The DIY is Do It Yourself if you didn't get it.


I have been working on these Philips 53" projectors that I got in with high hours on them (but low wear on the tubes) They have Hitachi 180DNB22 tubes.


All of these projectors work, but the focus was horrible and maonly blue and green images had this terrible halo around them. I says to meself, this looks like tube fungus, but the Hitachis are built differently than the Sony Sd-187's.


So I pulled a tube apart tonight, and found that the cooling fluid had completely discolored in the B and G tubes. The emission and focus of the tube itself was fine.


tomorrow I buy about 6 pints of cooling fluid and I'll bet the problem is solved.


I also noted that these Hitachi tubes use about 5X as much cooling fluid as anyother 7 or 8" tubes I have ever seen. Makes me wonder what would happen if Sony, NEC and MEC had doubled up on the cooling fluid chamber on FP tubes. Would the resulting lower glass temperature have increased the life of the CRT?


Hmmmmmm...


Curt
 

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Yes, I've had that same problem before. Once you replace the fluid the set will look like new. The fluid used in those tubes started to go bad from day one. The Hitachi tubes (if no serious wear) in that set should perform very well for a long time.


I wish other CRT's were that easy to fix.
 

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Talking in terms of the 7 inches Sony family, it is not very difficult, to get a bigger cooling chamber between the front surface and the real tube surface.

It's just needed that when you de-fungus the tube you put a thicker silicon layer all around the front metal fame, and then put the glass in place without to push too much (applying a very low pressure on the surface).


It's possible to obtain tubes in which you will fill some 1.5x amount of ethylen glycole, compared to the original ones.


In any case, it will be required a very long time, in order to understand if the "overfilled tubes" will obtain better results, in terms of timelife... :(




Romano
 

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Discussion Starter · #5 ·
Hey Rob, I buy it by the pint. GC Chemicals has it as do other companies. If you cannot find it, I'll send you some.


About $20.00 USD per pint or so.


Curt
 
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