Im considering a Marquee ultra.
What are frankenyokes. Are they preferred for all 3 guns. Who makes them, who sells them. Thank you!!

Excellent choice Alan, you have entered a whole new world!

A Frankenyoke is modified Sony 1292 yoke that it works in a Marquee and greatly improves focus/sharpness and allows contrast to be run higher over the stock yokes. Its a big improvement, probably the easiest and most rewarding singular mod other than getting the right lenses if your screen is over 7 feet wide (HD10F from a Sony 1292 or better still HD10F from a G90). Theres no ifs, buts or maybes, you need Frankenyokes!

Best to have them in all 3 tubes.

You can make them yourself but its getting hold of the right donor yokes that is the problem. Rarely come up for sale and are snapped up very quickly if they do. Easiest and cheapest way is to buy a used toasted 1292 and hope the correct yokes are still in it and then make the Franken yokes yourself.

Going rate is about $500 a set (extortionate but thats how it is).

There is an excellent thread about Frankenyokes entitled "Everything you need to know about Frankenyokes in one shot" here on AVS I think.

Edit - just did a search, its at the other place. It is without a doubt the definitive account of how to make/obtain Frankenyokes, what they do and why you need them.

Edit 2 - Found this on AVS http://archive2.avsforum.com/avs-vb/showthread.php?t=738387&highlight=frankenyoke but the one elsewhere has vastly more information, detail and is upto date, the one linked above is only a small taster and not really current (sorry).

Paul

Paul, how do you know if the yokes are the right ones? Should there be a number on them somewhere? Which ones should you stay away from?

Thanks!
Doc

I can see why these would be in demand and so scarce. Thanks for the info Paul.

The Sony part number is 1-452-811-11 The important bit to look for is code KD 22-22 on the yoke itself but its not always there. See http://www.avsforum.com/avs-vb/showthread.php?t=948145

I'm not an expert on how to make these or anything, I bought mine ready made from someone (who only made the one set). There are some folks around on this forum that have made them and there is a lot of information kicking around, do a search for Frankenyoke and see what pops up :)

Arghhh. I caved in and did a search myself - try this search result (hope it works) http://www.avsforum.com/avs-vb/search.php?searchid=11452202

Frankenyokes can be made from other yokes such as from a G90 but who would part out one of those and at what price? I think yokes can also be made from some Ampro yokes (22-11 ??), maybe some of the experts can chime in on this. The 1292 22-22 yoke is the acknowledged best for the Marquee and thats the one to aim for as it works very, very well.

There is perhaps another source for Frankenyokes but its maybe best to let the owner of that project speak about this himself if he wishes to do so.
Paul

Is it possible to modify the original Marquee yoke or is it simple an inferior product.

Not so much inferior, just different and not as easy to get the best out of it. You really need to get the stock yokes out of there and get the Franken ones in as they are more effective and make astig easier.

But no, the stock yokes can't really be modified. I think that the attempts to do so were more hassle than it was worth (its all documented you know where) - C M Johnson pioneered Frankenyokes and went through a few iterations before hitting upon the 1292 yokes. A stroke of genius I must say.

Let me try to put this into perspective with regards getting these yokes. If your Marquee does not have them, you will still enjoy the pq from the Marquee, its very good as is! Having the Frankenyokes will add a good deal more snap to the pq but won't make a bad movie good! Its not the end of the world if you don't have them - but they are nice to have.

Keep your eyes peeled and get them when you can - took me a year!

There are more critical things that a marquee needs before getting the yokes but again, I'll let others raise this as I'm not an expert on these, I merely follow the lead of those that are.

Sorry, I should have asked this earlier. But do all 1292s have the 22-22 yokes or do some of them have different ones. And where is it marked at on the yoke? Do you have to remove them to be able to tell?

Thanks!

Doc

I think that all 1292 yokes are KD22-22 but I'm not 100% sure - anyone know??

Here's a picture of my yokes - you can see the Sony part number 1-452-811-11 and then another number below - what the bottom number means I don't know but the part number is probably the same for all KD22-22 BUT, I don't know for sure I'm afraid.


http://i239.photobucket.com/albums/ff170/BorisBlank/Frankenyoke.jpg


You would certainly need to open up the 1292 to see the yokes but I don't think you would need to remove them to check.

Alan , the Thompson yoke(marquee), is not as an elegent design as the Kanto denshi (Sony,Barco,ampro,NEC)yokes. But only the Sony 1292 focus yokes and to some extent the sony G90 yokes are usefull as is, with only a connector/cable modification. The Ampro yoke have been used as well but these do not have the astig windings, these are mostly labeled KD22-11. But the lableing is not always the same as you can see from Pauls picture above. I think the barco yoke can be re wound to the Inductance needed for the Marquee focus electronics to work correctly, Also even the Sony yokes are not the exact same inductance as the Marquee's and I have a feeling a rewind of the Sony yokes would yield even better results. The thing that makes the frankenyoke so much better is the length of the magnetic field that the electron beam travels through on its way to the convergence and deflection coils. Its much longer than the Thompson Yoke's. And another plus is the proximity of the astig windings tot he electron beam, its much closer than the thompson yoke and also runs the entire length
of the focus coil as with the Thompson Yoke it is at one end of the assembly. One of my projects is to rewind the coils of the barco yoke as i think the magnets have the same gauss or very close where the correct winding inductance will off set any weakness the barco magnet may have over the sony magnets. Lots of other stuff on my plate but i do plan to investigate this more.

Athanasios

Thanks to all. This morn I knew nothing about what these were other then the funky name. Inst there a comedian Al Franken :)

To bad someone has not taken advantage of the demand for these things keeping stock. Theres a lot of Marquees out there.

Hi Allen, here's a copy of some info I posted from another thread
awhile ago, referring to some tests Terry and I did here on the 1292
focus coils compared to the stock units.
________________________________________________________
Found the notes from our tests last year of the stock Marquee vs.
the 1292 Focus coils. And, it turns out - we did the first run on
the 8500 down in the shop - Good Results on the 8" projector!
So, for crt_nut looking to do this on an 8" Marquee - Go for it!

Here's the results for both machines:
_________________________________________________________
Contrast ___% decrease line width 8500___% decrease 9500
-----------------------------------------------------------------
=40 ------------ 12% ----------------------- 18% -------
=50 ------------ 12% ----------------------- 26% -------
=60 ------------ 33% ----------------------- 37% -------
=70 ------------ 43% ----------------------- 33% -------
=80 ------------ 41% ----------------------- 39% -------
=90 ------------ 47% ----------------------- 48% -------
=100 ----------- N/A ----------------------- 54% -------
_________________________________________________________
-----------------------------------------------------------------

When I later moved the 1292 coils ~8mm further forward on the tube,
(by removing the conv yoke clamp and some tricky machine work), I was
able to improve the focus with the 1209 coils even more, especially out
on the sides.
__________________________________________________________

If these parts are hard to come by on the second-hand market, has anyone tried to order them new as spare parts direct from Sony?

one yoke for the G90 which can be used is like 1200. I do ot think they have 1292 any more.

Nashou

I do ot think they have 1292 any more.

Nashou

I did find some listed here (although no stock of course) http://www.nexttronics.com/catalog/sony/1/145281111.htm - at $487 each I'd doubt there there were many takers!

I found out how rare these things are, very hard to come by. I think Paul better lock those in a safety box, there almost as good as gold.

Some times its cheaper to buy an entire 1292 and part out the rest, I do feel confident i will be able to make some from Barco focus coils from the 1208 and 1209's I just need time and more ambition to do it. And if the magnet its self is not powerfull enough i may be able to coax TSE his Magnet calibrator to magnetize them or ask if he can tell me how to make my own , it looks like a Isolation transformer coil where you put the focus coil inside the conter of the coil while you run current though it.

you can see the variable transformer in the back ground he uses to probably pic the right current
to go through the gauss coil.

TSE's Gauss machine!!!!!
http://www.curtpalme.com/forum/files/gauss_255.jpg


Athanasios

If you think that the KD22-22 focus coils are cool, wait till Galen lets you in on his next mod.

Terry

If you think that the KD22-22 focus coils are cool, wait till Galen lets you in on his next mod.

Terry


ouuuu intriguing !!!

nashou

If Barco focus coils are any good to you I have about 3 sets available,


Terry you are such a tease !!!

If Barco focus coils are any good to you I have about 3 sets available,


Terry you are such a tease !!!

I'll let you know once i finish the static winding and put it all back together and get the wiring right, I am not sure if the flow of the current will matter much, i guess the only way to see is to try.

Athanasios

If Barco focus coils are any good to you I have about 3 sets available,


Terry you are such a tease !!!

And if AmPro coils are of any use to you Tough yitties. I'm keeping all my factory ultra tight focus projectors in tact.:D