[CRT_Ben]

I've been working on this for the past day, solid...I'm only running one LUG at the moment as I haven't modded the other two neckboards, and I just can't get it to focus like it should. The other two tubes (180DMB's) focus fine. If I adjust flare and stig correctly, I can barely get scan lines at 480p. Here's a quick breakdown of what I've tried:


-Tied Grid 3 (KH) to either 1M, 1/2W resistor to Ground, or directly to Grid 1. I noticed no difference between the two.

-Tried the stock (8") Thompson focus yoke, at different positions all up and down the tube (I have only tested stock orientation)

-Tried a 1292 yoke (frankenyoke) in both orientations, at different positions all up and down the tube

-With both focus yokes I even removed the convergence yoke to see if moving it up farther would help - it doesn't.


At this point I'm running out of ideas - this tube is basically new, the bell is very silver-white. It should focus just fine. Help!!

Thanks,

Ben

 

[Chuchuf]

Ben,


Forget scanlines for a moment.

What are your test patterns (crosshatch or dot's) looking like?

If moving your focus coils up and down the neck are not effecting the focus (I believe they should) I would wonder about the focus board or focus coils and their operation. Are you sure you are plugged into the correct socket on the focus board?? Are you getting focus in and out when you go to pic 4? how about electronic focus?


Terry

 

[CRT_Ben]

Hi Terry,


If I adjust flare, stig and EM focus as good as I know how the internal test patterns look just "ok". Most of the time it looks like there is a slight "halo" around things - like a vertical lines appear as a bright line in a flare, and dots appear as a bright spot in the middle of a flare, as if underfocused.


Then I switch to one of the 8" tubes and it's like I put my glasses on, there is a huge difference. I only mentioned scanlines because at 480P the scanlines on the 8" tube are almost as big as the lines drawn - but on the LUG the scanlines are tiny gaps and the lines drawn are much thicker.


I should have been clearer about the location of the focus coils - it does affect focusing, greatly so. It seems to affect how much I can under- and over-focus. But even if I put it roughly in the middle so that best focus is around 50, it is still not sharp. I have double checked the connectors to the focus board and they are on correctly. Both Pic->4 and RGB focus work as they should (though the LUG doesn't seem to respond quite the same way as the 180DMB's, but I expected that) - but when the focus coil is positioned correctly, I can over/underfocus. I just can't focus!

Thanks for your help,

Ben

 

[Chuchuf]

Lets look at the obvious first.

* bad glycol?

* CElement problem?


When you mounted the tubes in the housings how did you do it?

I'm not familiar from a P/N point of view, but it sound like you are converting an 8XXX series to a 9500? Is it possible that the magnetics on the 8XXX you are building from are causing an issue?

If you disconnect the focus coil, what happens to the dot or line?


Is it possible that these tubes were "rejects" and that is why they won't focus?


Terry

 

[CRT_Ben]



Quote:
Originally Posted by Chuchuf /forum/post/0


Lets look at the obvious first.

* bad glycol?

* CElement problem?

Glycol - I filled the housings with new glycol bought from MCM, the TechSpray brand as the RCA is backordered. The stuff looked pretty clear.


CElement - I pretty carefully inspected and cleaned the C-elements before potting the tubes in, so I don't think that's it.

Quote:
Originally Posted by Chuchuf /forum/post/0


When you mounted the tubes in the housings how did you do it?

I used GE Silicone II, the Gray kind for Aluminum. I put a thin coating on the housing plate that faces the tube, and filled it around the sides.

Quote:
Originally Posted by Chuchuf /forum/post/0


I'm not familiar from a P/N point of view, but it sound like you are converting an 8XXX series to a 9500? Is it possible that the magnetics on the 8XXX you are building from are causing an issue?

It's certainly possible. I believe that tse had said that the focus coil differed between the 8" and 9" versions, but what puzzles me is that the 1292 yoke has almost identical behavior as the 8" stock yoke. I believe that everything else - CPC magnet pack, convergence coil, and DY are essentially the same.

Quote:
Originally Posted by Chuchuf /forum/post/0


If you disconnect the focus coil, what happens to the dot or line?

Good question. I have to run out, now, but I'll try that tomorrow morning. What should happen?

Quote:
Originally Posted by Chuchuf /forum/post/0


Is it possible that these tubes were "rejects" and that is why they won't focus?


Terry

While I'd rather not think about this, it's crossed my mind

I tried the Red LUG in place of the Green one I was running last night, and it seems to focus better. However I did find a new way to set the flare that seems to work better as well, so I'll have to try that on the green. The red is about 90% as sharp as the AC tube in the corners, showing defined scan lines at 480p but probably 65-75% in the center, with scan lines barely visible.


Thanks,

Ben

 

[Gino AUS]

Are your G2 and drive settings set correctly for the tube?

 

[CRT_Ben]



Quote:
Originally Posted by Gino AUS /forum/post/0


Are your G2 and drive settings set correctly for the tube?

Hi Gino,


As expected I had to lower G2 and Drive significantly, I'm currently running G2 at 50 (set off the grayscale ramp) and Drive around 25-30.


Thanks,

Ben

 

[Chuchuf]

Are you still not able to focus with G2 and drive lowered?


Terry

 

[nidi]



Quote:
Originally Posted by CRT_Ben /forum/post/0


Hi Gino,


As expected I had to lower G2 and Drive significantly, I'm currently running G2 at 50 (set off the grayscale ramp) and Drive around 25-30.


Thanks,

Ben

the G2 settings are much lower than on P19LCP's


I just converted to LUG's on my Ultra last week.


brand new tubes (thanks Terry & Greg E.)


here are my G2 and drive settings:


Red G2 44

Green G2 40

Blue G2 37



Red Drive 33

Red sub brite 20


Green drive 90


blue drive 23

Blue sub brite 75




Michael

 

[CRT_Ben]



Quote:
Originally Posted by chuchuf /forum/post/0


Are you still not able to focus with G2 and drive lowered?


Terry

Hi Terry,


I lowered G2 and drive first thing after I started it up because the raster was shining like the sun

Quote:
Originally Posted by nidi /forum/post/0


the G2 settings are much lower than on P19LCP's


I just converted to LUG's on my Ultra last week.


brand new tubes (thanks Terry & Greg E.)


here are my G2 and drive settings:


Red G2 44

Green G2 40

Blue G2 37



Red Drive 33

Red sub brite 20


Green drive 90


blue drive 23

Blue sub brite 75




Michael

Hi Michael,


Thanks for giving me your numbers! Now I have a set to compare against to see if mine are reasonable.


One question - How do you set sub brite on the Marquee? I've never found it.


Thanks!

Ben

 

[nidi]



Quote:
Originally Posted by CRT_Ben /forum/post/0


Hi Michael,


Thanks for giving me your numbers! Now I have a set to compare against to see if mine are reasonable.


One question - How do you set sub brite on the Marquee? I've never found it.


Thanks!

Ben

I have a 6.0.1 software running on my marquee ultra.


older software didn't have the sub brite settngs , maybe yours is older than 5.0 ?



Michael

 

[Gino AUS]

So is the switch from LCP to LUG worth it? Care to give your impressions, advantages/disadvantages??

 

[CRT_Ben]



Quote:
Originally Posted by Gino AUS /forum/post/0


So is the switch from LCP to LUG worth it? Care to give your impressions, advantages/disadvantages??

Hi Gino,


I'm actually converting from 8500 AC to 9500LC, so I don't have any experience with the LCP's.


Michael, I believe my software is 4.something, but I'll check and report back.


I had a bit of a panic attack today, because my red tube leaked a bit of glycol overnight (upon draining and dis-assembly I found I had sealed the C-element incorrectly by overtightening the ring that holds it) and seemingly as a result I was getting a LVPS error when trying to power the set up. I opened up the LVPS and checked fuses, reseated connectors and now it's fine....whew

I don't know what happened, but glad it's working again.


So, I'm just getting around to doing more testing on focusing, etc. Terry, I'll try leaving the focus coil unplugged and see what happens.


Thanks,

Ben

 

[nidi]



Quote:
Originally Posted by Gino AUS /forum/post/0


So is the switch from LCP to LUG worth it? Care to give your impressions, advantages/disadvantages??

i can't comment on brightness, I had a P43 green which was very dim


but was told that the LUG's a re slightly dimmer than P22 LCP's


maybe 10-20%.


my P43 green only had around 7 ftL , with the P22 LUG green I get 14.5 ftL.


on my 96" 4:3 Stewart Studiotek 130


picture is sharper, much sharper than with LCP's and I don't need to defocus blue


for color temperature and gamma



Michael




Thanks again to Terry and Greg E. for the tubes

 

[CRT_Ben]

Ok, so maybe not all is well with the PJ...it started up and ran once after I installed the LVPS, but the second time it wouldn't start up. Here's what it's doing:


Press power on the remote, and the set starts up just as normal until it gets to the very end of the "HV Crackle" (but no erroneous sparks are heard or seen) then the set shuts down, briefly lighting the LVPS error code on the back. The LVPS then has the -15V error LED lit. I'm going to start taking things apart so I can see if I missed any of the glycol (it didn't lose much, but that must be my problem). Is there anything in specific I should look for? I think I recall that at least the Vert. Deflection board uses -15V?


Thanks,

Ben

 

[CRT_Ben]

Ok - this is kind of weird, at least to me.


Three times in a row, now, I'll reseat the LVPS and the set will power up and operate just fine, for as long as I want. Then I shut it down, and it won't start back up again until I reseat the LVPS. However the -15V error LED is not lighting anymore. Why, if everything is apparently functioning well enough to run the set normally, won't it start up??


Also I investigated further and it doesn't seem like the gylcol got anywhere. I see no trace of it in the power supply or on the mobo.


Thanks,

Ben

 

[Curt Palme]

Check to see if glycol dripped down the backplane... not the motherboard under the tubes, but the one that sits vertically that the motherboard under the tubes plugs into. That could be causing what you're seeing. There's an 8 pin system control chip on that backplane, and if glycol got under the chip or the 64 pin connectors, you could be screwed. It's about a 3 hour job to pull that board outta there, clean it, and reassemble it. I've got spare backplanes here if you need one.

 

[CRT_Ben]

Thanks for the advice, Curt. I thought that the mobo under the tubes was it, I didn't know that there was something else there (the backplane). So if I'm understanding you correctly, the backplane is kind of parallel to the back face of LVPS, but on the other side of the metal box that holds the power supplies?


I have to go out for a few hours but I'll look into this tonight and see if I have the time to take it all apart. If nothing else, it'll be a good learning experience!


One question - I know that gylcol doesn't evaporate, so if it's damaged something on the backplane, I should be able to see traces of it, yes? Does it discolor anything, or other telltale signs that I should look for besides the liquid itself?


Thanks,

Ben

 

[Chuchuf]

Ben,

Glycol as you said doesn't evaporate and when you try and wire it up, it smears rathr than absorbing in the paper towel.

It cleans up nicely with water or alcohol.


Terry

 

[CRT_Ben]

OK- finally got the time to take apart the PJ.


I'd love to say I found a smoking gun - but the ONLY glycol I saw was a bit of residue under the lower tube mounting plate, which is consistent with how much the tube leaked (very little). Currently I have the Mobo off, but I haven't taken out the backplane because I don't want to if I don't have to, and it doesn't seem to be the problem. It's entirely possible that the LVPS croaked because I was cycling the set a lot, trying to figure out my focus problem.


The trick of reseating the LVPS to get the PJ to start up no longer works. Any ideas? Does this point to the LVPS?


Thanks,

Ben