CurtPalme.com Home Theater Forum

[stefuel]

Well I'm still banging away at this. There have been a few other issues with this projector ever since I've owned it. One of which is a occasional bumping up and down in the image. The other is convergence at the extreme left top and bottom corners. tse told me that I should be able to work that out from within the PLL board. The instructions for that is on page
9-28 of the service manual. I was getting no where with that and was about to abandon it and put the metal cover back on when I noticed a burn spot on the inside of the metal cover. using that spot as a guide, I located a spot on the PLL board where a 1uF 35V tantalum cap used to be. It blew right off the board. I could not find anything else wrong so I replaced the cap and re-installed the PLL board. NO image shake. I did a 29[code] and re-did the setup for 1080P and it's almost perfect. I'm taking a break then I'll try the "registration phasing" procedure again and see what happens. I'm not going to break out my colorimeter until every bug I'm aware of is resolved. I did swap out neck boards again with the one that was streaking and the snap is gone. I adjusted a variable cap on the neck board and have almost completely eliminated the streaking. In the mean time, I'll look at the board I took off to see what can be done to eliminate the snapping.

I am close. Very very close

[Nashou66]

Awesome!! I cant wait till your done and watch a few movies and let those High Resolution tubes ease into use after the burn in phase.

this tread has got me excited again about the tubes and I just went out and bought some VHT satin Black Epoxy paint. The Krylon I used did not hold up to the Glycol.
Hopefully htis will, I let it cure for 7 days before i put on the bellows and fill it with Glycol.

Cant wait to see your results. I know you dont like screen shots but at least one of some sort of pattern!, even a simple Grid pattern!

Athanasios

[stefuel]

As soon as I get it the way I want, I will post a picture that will blow your socks off. It is looking better now than it ever has but I know there's more to be had. As soon as I get these left hand side top and bottom corners tightened up I'll calibrate the color and post a few pictures. I'm certain this projector with the Thomas tubes will color calibrate just fine. Heck, I've got it close by eye. I've gone this far with it. I'm not going to short-cut now.
The frigging thing will probably blow up tomorrow

[Nashou66]

[stefuel]

OK, I've beat this thing to death in a attempt to drag out whatever I can electronically and optically. I have got it better than it has ever been. One thing that I've been missing is a electronic adjustment that evens out the left and right electronic focus which in turn evens out the top and bottom electronic focus which I was unaware of. AmPro's biggest problem is it's inability to optically focus in the bottom corners when ceiling mounted, mostly seen on a 4:3 aspect ratio. On widescreen you can hardly notice it as it's out of the area that won't focus. I've got it so close now it's scary sharp. Tonight is color calibration time then put everything away and enjoy:thumbsup:

[mp20748]

[stefuel]

[Kiev Savoie]

Wow! Great project! I'm interested to see how it all turns out!

[Nashou66]

Ok Chip, how did the calibration go? i assume it should be redone after about 100 hours so the tubes have time to settle in.

I'm glad my tubes are being used in another PJ beside the marquee.

Athanasios

[stefuel]

I'm having a problem with my colorimeter at low IRE and I have to resolve it prior to full calibration I am able to (by eye) set the low end for a decent 10-50 IRE and the meter is working fine for 50-100 IRE and is spot on.
I'm still having trouble with the left side convergence at high resolution (1080P) and I think the problem is somewhere in the convergence tray. If you look at your 3600, the convergence tray is made up of 4 boards. The middle board is the waveform/blanking/OSD board. On that board there is a spot for IC-11, IC-12, and C68-C72. On my HD version these are populated. I have about 6 spare complete tray assemblies but all of them are missing these components. They are not even listed in the older manual that I have. I think my left side curve problem lies somwhere in the convergence tray. This did have a blown off the board cap that I replaced so I think there is another component that is bad but where to look without a HD version manual to go by. I'm going to start another thread just for this problem. Perhaps someone will now the answer.

[stefuel]

OK, the pj is up and running. I'm going to let it go and check for stability.
I was reading a thread over at AVS about Greg's super duper LUG tubes. In that thread he states that He's never seen LCP's that perform well over 720P. How many here will go along with that statement??? I've seen some pretty damn skippy screen shots of test patterns with projectors using LCP's. I see no reason to agree with that at all. I'm not saying that the LUG's are not better but geese, to condem LCP's to 720P??? Sales pitch??? I smell something and it ain't burned resistors.

I can't compare the Thomas tubes to the LUG's because I've never seen one. They are sharper than the LCP's on test patterns but how much of that can actually be seen watching full motion video at any resolution is questionable.

I wonder how many here will go out on a limb and say they can tell the difference between LCP's and LUG's watching full motion video??? Too many here hold to much stock in test patterns. They should be used only for setup and service of displays. That "fine detail" that Greg is complaining about CAN be seen in test patterns but most of that detail just does not exist in the crap that comes down the pipe that we feed our projectors to watch.

I for one feel that LCP's are just fine for HD full motion video. Is this a home theater forum or a home test pattern forum?

[cmjohnson]

You're putting all that time and effort....into an AmPro. ;D [lol]


AmPros always have focus issues in the corners. That's because their method of implementing Sheimpflug on an LC system is both
unique and technically wrong. 3M intended that the C element is to stay in rigid correct alignment with the len, and the CRT is pivoted
behind the C element. While the AmPro C element and chamber has no leaking issues, it's optically flawed if any lens tilt is dialled in at all.

Incidentally, the AmPro prescription C element is not the same as the C elements used in any other PJ. Don't interchange them, because it won't work. It won't focus.


As for sharpness, a fresh set of LCPs that are fully dialled in are plenty sharp enough to resolve 1080p, with reasonable MTF values,
even with stock focus yokes on a Marquee. With the K-D focus yokes in an AmPro, they should be capable of every bit as good performance, or better.


CJ

[Elaine Benes]

[stefuel]

"Incidentally, the AmPro prescription C element is not the same as the C elements used in any other PJ. Don't interchange them, because it won't work. It won't focus."

I don't know where you heard that. I've never been aware of anything of that nature. I have a standard red c-element in my 4600HD that has perfect focus. I have two greens, both in AmPro housings. One from a Marquee and one original to a 4600. They both seem to focus the same.

The only place I see optical focus out of whack is the bottom corners on a 4:3 screen and those areas extend up about 4 inches from the bottom and about 6-8 inches from the side. I use a 4:3 screen and when I input a HD aspect ratio, the bottom corners are well above the areas that will not dial in correctly in a 4:3 aspect ratio. If the projector is set up correctly and the electronic focus balance control is optimized, the limitation of AmPro's LC's is of no issue.

[Nashou66]

On Another note, I tried VHT Brand Epoxy satin Black Paint for the Marquee LC chamber. Many marquee's LC chambers anodization gets eaten away and the exposed aluminum gets exposed and corrodes even faster. having said that, i have the original Green Thomas test tube in this housing now and put on my repaired HV lead as well, so this is a full experimental tube let say. Tonight i will fire it up and see how well everything works on it. its in my Work Shop so I have no screen to test it on for focus. But i plan to in the near future.

I let the paint dry for one week and it is a nice hard finish, harder than the Krylon Enamel paint i used before. I think this paint might be the solution. I need to find Flat Black i think but this should be better than the Greenish Grey of the original anodization.

Athanasios

[stefuel]

I don't think it needs to be flat black as when wet it will have a shine to it. I do think you can get appliance paint in black. That is suppose to dry super hard. The other thing that comes to mind is model airplane paint (Dope), it is impervious to nitro-methane so I don't think antifreeze will touch it. You can get it in brush or spray cans.
I do have one AmPro LC casting that you can tell was re-coated with something. It held up but I have no idea what was used.

[Nashou66]

This is the stuff I used:



Athanasios

[Spanky Ham]

Interesting, as I have been thinking of painting the inside of my G70 chambers. I still believe a combination of masking inside the chamber and a good anti-reflective coating would send the MTF and ANSi to much higher levels.

On the LCPs, why would VDC sell and install them if they could only do 720p?

[Nashou66]

well so far its been almost 3 days with the Glycol and its holding up nicely Spank. Black is much better than the grey for the Marquee's I think.

the tube is not in the machine so I really cant test on the screen( and the way its set up I cant focus that close if I had a screen) . I am also playing with my Barkenstien yokes on this tube. its been so long I forgot how i had things wound inside the yokes. I have to start over with more detailed note taking this time around.

I'll keep things posted here on the paint.

Athanaasios

[km987654]