CurtPalme.com Home Theater Forum

[dvh99]

http://stores.ebay.com/Brocotts?_trksid=p4340.l2563

ebay store located in the uk.

[andreas]

ah, steve, this wont be the case since the yoke has already been picked apart. I can already pick everything out from that yoke because it was in that condition when i bought it from curt(glue does not hold the parts). The othet two has not been opened. Im going to look into this more tomorrow.

[mr_ro_co]

[Nashou66]

[mr_ro_co]

Guys, based on the discussion so far, I have updated my drawing. Please review and verify.

Thanks,

Steve

[andreas]

Ive tryed to messure all the red marks on the picture below. I get nothing and i can not see any damages on the copper wiring. If it has been broken deep beneth i have to rewind the whole coil to reach it. when doin messurment, does the coil have to be in its place(with the magnets over it).

possible options 1: put the old thomson yoke on the blue and see what hapens(even if it works i wont be able to run the contrast as high as i want). Do you think there is risk of damageing the PJ?

2: take the wiring from the tomson focus yoke and put it on the sony focus yoke, wild thought i know it may not even fit in....

3:part out the projector

[Nashou66]

For now just use the old focus coil. it wont do anything bad. Also the Blue tube should be de focused for proper Greyscale anyhow.

You do know the wire in the focus coils is covered in Clear enamel. DID you make sure you cleaned it off before you connected the
harness wire?

Athanasios

[andreas]

Athanasios! I did nor know that. I polished it with the easiest sand paper and... I got contact! i repeat, ive got contact hahaha

[andreas]

Ive powered up the PJ. Better, but still as when i begun. the center is out of focus. the magnets had been marked with a V so i put them back after that marking. When using the old tomson yokes the best focus for G was 51, R 38 and B 29. I dont know if that has to do with it. Seems to be the same here, green can be just a litle overfocused and red is just about the best focus point when the adjustment runs out of range(about20 for all guns). and the blue is far from its goal. if doin the overall focus green starts to bloom when ramping down to about 45 but red is not afected after passed 50 and the lines does not spread out.

The blue yoke is naked but the R,G has their shells on. could that matter? thanks to you all!

Sorry about the spelling. The spellcheck function does not work from here.

[Nashou66]

On thing I did with the Barco yokes I rewound and the Sony 1292 Yokes was to ream out the edge that goes up against the
convergence Yoke. Remove the convergence Yoke clamp and then slide the G90 focus yoke you just reamed out a bit on that end
so it goes over the clamp flange and no sits right up against the Convergence Yoke. you gain about 1/4 inch towards the face of the tube.
sometimes this reduce distance towards the bell housing helps get a better focus. The best thing to do is remove the connections
and slide the focus yoke up and down the tube till you see best focus and leave it there. You now have the best static focus the magnets can get with out help from the coils. Now after power is sent through the coils the range will be optimized for that magnet structure.
I am not sure what the optimum Gauss is for the marquee focus system but this will get you as close as possible with what you have at hand. The best possible focus would be if you had many yolk's available and tested each one in this fashion to get the best focus yolks of the bunch to work in the marquee. Unless you know where on the Focus board to make changes and like Math to figure it all out.

nashou

[andreas]

thanks for the tips! I carved out the plastic so the yoke would slide over the convergence clamp for blue. Still no improvement. Then i pulled out the electric focus plug for both blue and green to compare and the blue lines are significantly thicker than green even with the electricity unpluged. One thing is that with no electricity conected the grid is thicker in the center

/andreas

[Nashou66]

ok swap focus yokes between blue and green to see if its the yoke

[andreas]

I did swap them and the problem apeared on green instead. The same with the focus, it stops about the same point. When reaching 20 the lines stays at the same thickness down to 0.

[Nashou66]

[andreas]

thanks for your replyes! I think ive tried everything now and ive taken off the neckcard so many times im startimng to worry of breaking/bending the g-2 pin or something else.

It probably is as you sugested with weekend magnetism. It just seems wierd that the problematic yoke is the one that had been opened up and taken apart when ive got it. just saying...

I know that blue is not as importand and even should be softer BUT since im planing to run the contrast at 60(i dont have a completely dark room) the blue would bloom to much at that contrast level so i dont think it will be possible to run it that high. The marquee manual says that contrast level should not go beyond 50 because the blue will saturate... maybe it will be okey anyway.

Perhaps i wont be wining after completed the setup for red and blue. The dotshape is AMAZING compared to before after a rough adjustment. And again, thank you all for your awnsers

[Nashou66]

I run my contrast at 72 with the Thompson Yokes.

Athanasios

[htguy1]

Hi,

Ok dumb question time... could the convergence yokes from the g90 be used on my 9500LC so as to keep from the g90 frankenyokes from pushing the astig magnets too far back? I just bought the complete set of g90 magnetics to get the focus yokes.

Thanks

God bless..
Mark

[Nashou66]

I know Galen tried the 1292 convergence yokes on a marquee but in the end went back to stock. Not sure why.

Athanasios

[cmjohnson]

I know this thread hasn't been very active lately.


I wound my Mark IIs to match Marquee coil inductance specs and did not get the results I'd hoped for. In truth I put a calibrated set of original Thomson yokes back in and just have been running with that for a while now.

But, I am back into experimental mode just because I want to make this work.

First, I selected one Mark II yoke and took turns off the static focus coil, to reduce the inductance by 10 percent. I then installed it in the PJ on green and
started to play around with it.

Best center focus is around 74 at the moment and there is a lot of interaction between the user focus adjustment and the service focus adjustment. Depending on where one is set, the range of focus adjustment available on the other setting varies quite a bit.

I'm shooting for 50 and 50 with a sharply focused center.

I'll have to take a few more turns off the static coil. I'm going to take it down to 24 uH, down from the original 30. I think that'll get the center in the right
range. Once that's been addressed, I'll look into the dynamic focus coils.

The basic magnetic strength of the Mark II coils seems to be in the ballpark. Unplugging the focus and astig cables gives a slightly out of focus image, but the outer edges are sharper than the central image. Considerably so, actually. But when plugged in, it's evident that the dynamic windings are too effective, even at a setting of zero. Going up from zero zone focus to 100 only makes the edges MORE defocused.

I'll take some turns off the dynamic coil after I've got good results from the static coil. My guess is that I'll have to take the dynamic coil down at least a good 30 percent.

Nash, what was your final and best result with Mark IIs? Where did you end up?

CJ

[tse]

If increasing dynamic focus from 0 to 100 makes the sides less in focus the polarity of the winding might be wrong. Try swapping the connection of the dynamic winding.

Scott