CurtPalme.com Home Theater Forum

[mp20748]

[mp20748]

[antorsae]

[cmjohnson]

I'm all smiles here. I haven't made a DIME off of these things, but I'm sure glad that I tried it..and found the
improvements to be worth mentioning.

Mike approves. Suddenly I feel a little taller.


CJ

[tse]

Posted for reference. The 2222 version focus mags have dynamic stig windings. A couple of pics showing the extra bobbin and windings in the 2222. There are two sets of four windings with one set arranged in a "+" fashion with the other set in an "x".

Scott

[antorsae]

Scott,

Is there any intention at VDC to upgrade the focus coils of the Marquee series with a better focus coils (at least equal in performance to the 22-22 ones)?

[Chuchuf]

I'd also be interested in hearing Scott's opinion of the 22-22 yokes when used in the 9500. I'm guessing you have a set based on that picture?
Some rough measurements we got was that the spot size was 20-50% smaller when measured over the contrast range 30 - 100. We also saw that the light was more evenly distributed over the line or dot that we were looking at with less flair.

Terry

[Joust]

[tse]

[tse]

[tse]

[mp20748]

I have a set of the 1292 focus coils here. I first tried them in my test 8500 ultra in the shop. I found pretty much What Terry and Galen found, that was that it produced a tighter and cleaner lines and dots. I since then put one in my 8500 in my HT on the green CRT.

In that set up with the one on the green CRT, I could compare it to the red CRT on my screen. For some reason I was having a problem with the green not focusing properly on the green CRT with the 1292 yoke. That was later to be found to be the CLM. Replaced the CLM and was back on track, but was not that pleased with NOT having the centering feature that the Thompson coils have.

And for me, that's very important.

I think the 1292 coils produce a very tight line. And for some reason, they also increase the light output. There were some things you'll have to get sued to with the subtle difference in how the range on focus adjustments have changed, but once beyond that, I guess things are great.

For me, I went back to the stock coils. For two reasons, one the 1292 coils did not belong to me. two, even if they were mine. I would have still removed them. I prefer the stock coils, because the same tightness in lines and dot can almost be achieved with the stock's if one knows how important it is to center the beam in the coils, when done right, that haze is a non issue. But as I said, for me, centering that beam is very important for me, and in how I setup a Marquee.

[CZ Eddie]

Well, I for one am not 100% sold on the focus yokes as I mentioned to you earlier, Mike. I'm getting spot size very similar with my late model thompson yokes, as compared with the sony yokes. I will not say yet that my focus is any better with the sony's. It's more difficult for me to compare, since I'm not a hot rod calibrator. But with your MP Mods, my thompsons seem to hold spot beam size about as well as the sony's when I ramp up contrast pretty high.

I'll probably hold onto the Sony's though and keep trying to discover it's secrets. Maybe Chuchuf can unlock some holy grail with them.

[cmjohnson]

Thought I respect Mike's position, I do want to point out that while you do lose the centering feature of the Thomson yokes
if using 1292 type yokes, you also shouldn't NEED the centering feature with them in the first place! Their magnetic
field seems to be considerably more uniform and predictable vs. that of the Thomson due to their design. Ring magnets
give a more consistent annular magnetic field than six magnets in a hexagonal array between two plates. Those six
magnets can vary in individual performance and the quality of their magnetic coupling to the plates can vary as well.



I have noticed that results do vary from one PJ to another with the FrankenYoke mod. Some sets of yokes just seem
to work better with some projectors, and that's all there is to it. I don't really know why.



CJ

[Chuchuf]

[Chuchuf]

[Curt Palme]

Guys, I have not been following this thread, but I was running through my 100 lb box of spare yokes and stuff, and I'm guessing that I've got one or three sets of these. Rather than me slogging through the 15 pages, can someone sum up a list of the yokes that will work in the Frankenyoke application? I'll post sets for sale when I find them in the buy/sell section.

And no, unlike elsewhere, they won't be $1400 a set..

[Curt Palme]

Guys, I have not been following this thread, but I was running through my 100 lb box of spare yokes and stuff, and I'm guessing that I've got one or three sets of these. Rather than me slogging through the 15 pages, can someone sum up a list of the yokes that will work in the Frankenyoke application? I'll post sets for sale when I find them in the buy/sell section.

And no, unlike elsewhere, they won't be $1400 a set..

[nomadII]

Curt,

A reminder that we just chatted via email.
thanks, mark

[tse]

If the mags have a four pin connector, probably just a static (high inductance) winding and a dynamic (low inductance) winding. The Ampro 2211 are this type. If there is a nine position connector the dynamic and static as well as "x" and "y" (low inductance) stig windings might be there. The 2222 type are like this. There are other number mags from Barco projectors.

The lack of stig windings is not a horrible fault when used with Thompson deflection yokes (Ampro and Marquee projectors). They are wound in such a way as to minimize asigmatism distortion in the corners. The Barco and Sony deflection yokes (Sanyo made?) have higher spot distortion in the corners and more need of dynamic stig modulation. Or so I was told once by a Thompson engineer.

Scott

[Gino]