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Discussion Starter · #1 ·
Hi, i'm at a stand still, i need your help. i have replaced the resistor and the big cap on the focus board. Hard reset was also done. My picture is unwatachable. convergence lines are extremely fat and out of focus. i have notice that the electronic focus, is working as it increases towards 10 it gets more into focus. this worked just the opposite before. so something is working. i used 3 15 m ohm 2 watt resistor and a 100uf 250 vcap. Can someone suggest something? thanks

* valuable lesson learned. i will do one tweak at a time.:)
 

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Discussion Starter · #3 ·
i noticed a strange thing happen when i shut down pj tonight. There's a quick white flash on screen then a blurred blue,red and i think green. (in a big circular pattern) flashes in the center of screen.
 

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It sounds as if one of your 15 meg resistors is out of spec, or it let go under th pressure. Also, the cannot be 'wound' resistor types. film types, solid substrate types, wtc. but not wound. I can't imagine 15 meg wound resistors.. but.. ya never know. It's the inductance that'll get ya.


The symptom of focus getting better at the END of the foucs (10) makes me think that the problem is the resistors.


Don't feel stupid. I've repalced over 100 capacitors on 3 boards..and then wondered why it didn't work afterwards. Find the problem ....with 100 caps changed. not fun... luckily..I had about 40 spare boards!
 

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If you have 07MS tubes, you'll need another 10Mohm in series for the proper value. As for the cap, can't help you there. Once you get the resistors straightened out, if you're still having problems, put the old one back in.
 

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Discussion Starter · #7 ·
well, i got another focus board all-together. i fired up machine and same results. nothing changed. (everything's blurry, all crts) i am beginning to feel a bit frustrated. Btw, i also upgraded the Dallas chip from ds1225 to ds-1225 Ad 150. I double check soldering job for error but didn't see anthing. How do i know it went bad? For the record, i was able to tell the difference when i installed it, (vertical lines on screen went away) but after i installed the resistor (on focus board) i started having problems with the focus. What should i do?
 

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Discussion Starter · #10 ·
i have also noticed that when i look directly at crt face R, G or B the image is very blurry (badly out of Focus) this is not looking through the lenses. As i stated, it's directly at the tube. Please help me out.
 

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Again, what CRT's do you have...did you read my post?
 

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Discussion Starter · #14 ·
Cary, i don't think i messed with the Focus pots. what do they look like and where are they located on the ecp-3000? Also can you confirm that by doing hard reset can it affect Beam focus/EM focue etc?
 

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Ahhh, then when you say "electronic focus", you mean the one on the remote right? The only effect that a hard reset has on focus is that the electronic focus via the remote gets reset back to "5". Now, the focus pots (potentiometers) are on the focus/bias board. There are six pots facing up on this board - G2 adjust and focus adjust for each color. The focus pots are the "big" ones. Try these if you haven't already.


Cary
 

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Discussion Starter · #17 ·
cary, i have already tried those pods (three black pods w/ white hard paper around them, color marked for b.g and R). focus is still terrible. lines are still fat and blanking is present.
 

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Discussion Starter · #18 ·
Quote:
Originally posted by jcmccorm
So turning the focus pots *does* have an effect on the focus? (although you can't get it completely focused).


Cary
i couldn't have said it better.
 

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O.k, let's go back to square one.....Was the focus any good prior to the resistor mod? Or, were you attempting to "fix" it by doing the mod in the first place? Since you have SD187 tubes you should NOT have an additional resistor connected to the flat focus resistor (only needed for the MS107 tubes). From reading your previous posts it seems that you backed out of the mod by replacing the bias module with another one, correct? This one has the factory focus resistor, right? Now, with the focus set to '5' on the remote (don't touch it again) put up a test # pattern and turn off the red and blue tubes on the bias module by sliding the appropriate slider switch on the top (near the focus pots). You should just have a green test pattern showing......Now, turn the green focus pot counter clockwise all the way and then start turning it clockwise slowly......Does the thickness of the lines in the test pattern start to collapse and then expand again the more you turn it?

Have you done any of the stigmatism and flare adjustments yet? It's possible that the flare adjustments are way out if the line does collapse and at least start to expand again......There are quite a few posts already about setting "stig and flare" so have a search around and if you still have questions let us know.....
 

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Discussion Starter · #20 ·
Quote:
Originally posted by Chris_Holmes
O.k, let's go back to square one.....

[1] Was the focus any good prior to the resistor mod?

[2] From reading your previous posts it seems that you backed out of the mod by replacing the bias module with another one, correct?

[3] This one has the factory focus resistor, right?

[4]Does the thickness of the lines in the test pattern start to collapse and then expand again the more you turn it?

[5]Have you done any of the stigmatism and flare adjustments yet?
1) yes... somewhat /needed improvement. At least the picture was watchable.


2)Yes... i backed out and had it replaced.


3)Yes... it does.


4)Yes.... although it collapses at "best focus" it is still out of focus(blurry) and thick.


5)No.. i haven't done stigmatism and flare adjustments yet, it will be my next project.


Thank you very much chris.
 
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