CurtPalme.com Home Theater Forum

[mp20748]

I'm using Barco 909 focus coils on my 9500LC Ultra. I've found that when I also had the Sony yokes on my 8500, I had to push the coils full forward to the deflection yoke for best focus. Much like with the stock Marquee yokes, the focus coil has to be as tight as possible to the deflection yoke.

So far, having tried three different focus coils on my Marquees, I always wondered if the spot where I had the focus coil was the absolute best place for best focus. I know when using the same focus coils in both Barco 909 and Sony 1292, the coils would have to be move to an exact position on the tubes neck for best focus.

So that lead me to try a full set of coils and magnets on my test 8500LC. In doing so, I had to modify the Barco 909 deflection yoke to the wiring scheme of the Marquee. The thing about the Barco 909 deflection coil i really liked was it's built in "Convergence" coil..

So I'm also using the convergence magnets built into the 909 deflection yoke.

When using the entire coils and Rings from 909 on the Marquee, It allows me more range to move the focus coil on the neck of the tube. And that allowed me to find a more precise sweet spot for the focus coil, which provided an overall better focus.

The only obstacle was that I had to adjust the convergence start pulses in the service menu to work with the 909's convergence coil.


I plan to also put a complete 909 coil/magnetics on my 9500LC this coming weekend..


I'm thinking you'll not need to go the route I'm going, if somehow you can find a way to move the focus coil more forward when using Frankenyokes you would reach a more precise sweet spot for the coil and that would make for better focus.

[Sparky015]

Mike, do you have before and after screenshots to show the difference on screen?

[mp20748]

[dvh99]

i would like to try that but where would i find the barco coils.

[Sparky015]

[dvh99]

i saw those too at niktec, thats a bit too much for a fun experiment.
there was a thread that discussed how to get the thomson yokes back to strength using a toroidal trafo.
if i get new tubes i may just do that if i cant get my hands on other coils.
i bet the thomson focus coils can provide enough focus when brought back to spec.

[Sparky015]

I saw that thread as well, but didn't think anyone had actually finished that project yet. That would be ideal

[mp20748]

Ok, I found the perfect combination without having to go with a different set of deflection yokes. Will need to find a way to stabilize the convergence and deflection yokes since the tightening ring has been removed.

I have a few ideas that I'm sure would would work, but need to find the material first...





Also, I found a very neat way to increase the horizontal width on a Marquee..

[dvh99]

mike do you have a magic hat where all those parts are coming from.
cine 9 focus coils deflection yokes red c-element.

[mp20748]

[dvh99]

you have 2 sets of coils somewhere lying around...
i guess there is no chance you are willing to sell a set.
end may i will have some money for your vim if you still have some. (tax refund)
1 thing about the banding mike.
how do i know if i have banding, are there test patterns that show me that.

[mp20748]

[mp20748]

Oh, I now have the coil setup showing in my last picture in my 9500..

removing the tightening ring puts the focus coil at the perfect spot for best focus. Without doing the stig and outer zone focus, the lines look amazingly good.



So I might finish this tonight. It sure looks easy enough.



I found out in an email chat with Scott, that when the coil is the right coil and placed at the right spot on the neck, both center and outer edge focus is easier to achieve. To even in some cases, either the center or out would yield good focus, but not both. I'm getting both, and I'm getting it exceptionally well..

[Mark_A_W]

" The thing about the Barco 909 deflection coil i really liked was it's built in "Convergence" coil."


Every projector I've ever seen has a combined Deflection and Convergence coil. And a combined Focus and Astig coil. NECs, Sonys, Barcos.


Ok, I've said it once, and I'll say it again. Marquees are weird.

[Drez2]

Hey Mike,

Do you think that the Barco 909 coils would help the focus of rebuilt tubes? I have a very nice Marquee 9500LC with all of the general mods, except I find that the resolution is still limited to around 720p. the focus coils are stock Marquee stuff. The tubes are low hour re-built VDC tubes from 2005.... Just trying to explore the best possible way to sharpen the picture for Blu-ray play back.

Dave

[tse]

[stefuel]

[mp20748]

[mp20748]

Here ya go Scott.

Just like I said, increased horizontal width at full 1080P 72hz - check out what the Horizontal size is showing at full screen at that rate..

[Sparky015]

Mike, your green looks stellar. Nice sharp focus!