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KBK said:
Yep. it's a short neck 8" panasonic tube. It might be common in the RP set arena, or simply uncommon, so there may be some new ones floating about for reasonable prices. After all, who wants to buy or stock rare tubes? QUOTE]


VDC had OEM at one time for $195.00. Now just rebuilds for $195.00. It is a crapshoot on the quality issue. With a little love and care the 1085 can throw a very nice HiDef image.


This is an image from my 1085. FWIW the camera used is Olympus 3.1 MP.

http://www.sweetwilliampress.com/lotr.jpg


Brenda - 800-241-5005 X140


Willie
 

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Discussion Starter #22
I'm not sure I believe for a second the 100hr 'pre-conditioning' burn thing. If this were so true, then RP manufacturers would have made some effort in that direction in the past 20 years. Someone would have used it as a selling point. I've never heard a word about it. I don't think 100 of tube destruction is nessesary before using a tube in a proper and useful manner. If this is specific to the rebuilds, maybe.


Thanks for the number. I'l try and see what I get. Also, I hear theyre is some other company I might call. Starts with a 'p'. praxis or something like that. Likely..I gave him the information in the first place!! I forget, It's been so long. They might be more likely to have the actual OEM tube. Paul (gn2) mentioned it when he was over and we got the PJ up and running. He doesn't have to buy a 1085 now, he says. He's seen mine.
 

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used to be called PATX at Tritronics 1-800-638-3328(Maryland branch.)refurbs.PATX.com
 

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Discussion Starter #24
ahh.. thanks Ron. That's the one I'm looking for.
 

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Discussion Starter #25
OK. Have my 1085 up and running with Gn2's help. He got a marantz reemote with the codes installed.


The PJ has burn on the red and green. Minor burn. Seems like it has low hours..as...hot damn! for what it is, this is a damn fine PJ!


PS, guys, I've already modded it a bit. Brought out the dynamics, detail, punch, etc. It was bothering me..and afterward..ahhhh..such a visual relief.


I swapped out 9 capacitors and Paul had only driven away 1/2 an hour earlier. already it was modded. :D :D can't help myself, when I know that a better PJ is only inches away from the soldering iron. Yes, don't try this at home: modifying PJ's while full of beer. Then I decided to pass out on the floor with the system still running. Just to complete the picture.


There are 3 bi-polar caps that the signal goes through on each color channel..before it leaves the input board. Crap! Crap! I swapped all of them out..and the dynamics punch, detail, saturation, contrast all went up a VERY noticable notch.


For most of you 1085 owners, it would be like owning a new PJ. It is now directly competitive with a mint Marquee 8000 in stock form, with this capacitor swap. Bright as all get out too, with those 8" tubes. And to add, it's damned fine on the focus, for an ES unit. Best ES focus Paul (Gn2) has seen, and he's seen most that are out there, period. With the color corrected lenses, it's a killer image for the money.


Now the cat is out of the bag! 1085 owners want this sort of thing hushed up :D


I'm now going to sand down the chassis, and paint it black. I will be selling this unit when I've put my Marquee 9500LC together, or G90, whichever comes first. If the price is right, I'll be putting new tubes in it (1085) first. I will be selling both chassis together, with one as the parts machine. This will be my 'hold me over' PJ until the 'big guy' comes along.
 

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Discussion Starter #26
Manuals, manuals, manuals.


Anyone got the tech manual for this 1085u PJ? I could certianly use it. I don't mind modifying blind..and I will 'iffin I have to. But I'd rather have the manual to do it exaxtly right. Less chance of failure that way. Heck, I'm not afraid to blow up brand new $10k (dealer cost, what I paid) DLP units..so this little peice of CRT fluff don't bother me too much.


Ok, so I nearly died when my brand new DLP failed to function after modding it. :D Luclkly, the fix was easy. Frightening, in that modified PJ's have no warranty and manufacturers can't fix it, as they aren't allowed to look at proprietary modification work. No fun when it's less than a week old.
 

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Discussion Starter #27
PATX just quoted me $1100 for a OEM NOS tube. Ouch. Possibly, they didn't like me or something.


Brenda jsut quoted me $295 plus $25 for the cor charge, re-furb, obviously.


Now I'll try to get all friendly and pull in some non-existent favors at Panasonic Canada. See what I get there. I'm a good guy. They like me..they tell everyone to use Goo, if they ask. So..we'll seee what comes of it....
 

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Ken,


I have hard a copy, however the schematic pages fold out to something like 11X17. I'll see what I can do to scan it later this week (like Wednesday).


Willie
 

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Quote:
Originally Posted by KBK
There are 3 bi-polar caps that the signal goes through on each color channel..before it leaves the input board. Crap! Crap! I swapped all of them out..and the dynamics punch, detail, saturation, contrast all went up a VERY noticable notch.
Hi


I'm very intrigued with this mod as I also have two 1085's. Did you use similar specsed caps or better ones? I guess these caps are easy to find on the input board as I have the schematics also. edit: I presume the ones you swapped were the blue ones: C006, C106, C206, C014, C114, C214, C028, C128 and C228. They seem to be rated 100uF, 25V and 85 degrees Celsius. What did you use for replacement?


How do you like the noise from 1085? I've modded mine to very silent, but the mods aren't all exactly invisible as you can see from this picture. There's some more pictures in here , note that some are old.
 

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Discussion Starter #31
Obviously, I used better caps. As usual, the bipolar characteristic is not that essential. It is essential in terms of rising vs declining levels. IE, the LCR characteristics of the capacitor will play a part in what you see. This is all obviously..high frequency, so LCR of the caps does come into play.


I simply threw a few in there as I had quite a few (over 200) lying about. What I used are Sanyo OS-CON polarized 180uf 20 volt capacitors. No issues, as I suspected. The LCR of these at high frequencies is extremely negligable..compared to the standard electrolytic 'wound' capacitors that were in there. THe dynamics and subtulty of the image went up a very noticable notch. There is also one capacitor right at the input of the boards just above the input board. A fourth capacitor. I swapped those out last night. Same improvement, and noticable. Modify at your own risk.


Next obvious one, is the input into the neck board,and the PS buffering on the neck boards. THERE IS NONE! the voltages come ontothe neckbaord where there is no local buffering. This is an issue. One that decreases dynamics and smears the image. Resolution should go up a noticable notch, after adding buffering to the higher voltage rails on the neck boards and adding a better signal coupling capcitor to those neck boards. It looks like it is a mylar (signal inout on neck board) cap right now. We'll see. I'm not going to spend too much time on this unit, as I do plan to get a better PJ soon enough. I've no real Idea how long I'll be using it, so I may as well enjoy my time with it.
 

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Sorry about this newbie question, but how did you figure out which way you put the new caps, I mean plus and minus poles?
 

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Discussion Starter #33
crap shoot. Do at your own risk. Instinct. I've blown enough stuff up to know which direction. etc. I can come up with more excuses, of you like. :D


It's really somethign I can't explain easily. Basically, you should be knoledgeable of waht a given circuit is..and then determine the polarity. Many times, a given cap in a circuit is used as a bipolar cap, but is really a polarized capacitor. One has to be careful. this is not always the rule and some circuits can be 'voltage biased'. If the cap is inserted wrong in such a circuit, it can cause issues. You will many times see polarised capacitors being used as 'coupling caps' on 'op-amps' in audio circuits. Quite common. In video, the voltages are low and the current is generally low as well, so the issues with using polarised caps in video signal coupling should be lesser than they are with audio.


The first and last capacitors in this line up, in this particular projector, are easier to deal with, it is realtively obvious, in terms of direction. Positive side on the input, negative terminal of the cap on the output.


I can't give specific instructions,and shouldn't. I feel it is something that people should do with their own skill levels and at their own risk, I won't involve myself in responsibility for their results.
 

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Discussion Starter #34
ES focus. Gah. I'm going to go after that focus. Try and repair it. Ot sharpen the PJ. In my opinion, at least 'coming into'; the idea of attemptng to 'fix' the focus issue of ES projectors, there is likely a way to fix the focus so it is sharper. THis would also apply to older projectors.


In older projectors, the focus on the ES units is said to 'go soft' In my opinion, as I stated, without looking to closely at the issues so far, It can be improved. I've fixed, or notably shapened the focus on Electrohome ECP series PJ's before, by messing with the focus boards and the focus assemblies.


There are very sound reasons for my preliminary postion on the idea of 'repairing' or drastically 'improving' the focus of ES units.


We'll see what can be done wit this PT-1085U PJ, and of the work is transferrable to the Sony's and the like. Right now, I'm sitting in a chair beside the PJ, and staring at it. Tracing the circuits back. doing basic measurements.


Once again, my expereince with -years- of modifying Tube amplifers comes into play.


Same-same.
 
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