CurtPalme.com Home Theater Forum

[Nashou66]

[Nashou66]

Scott you were right, on the very first Barkenstien Yoke I ever wound I reversed the static coil windings and it came right in. Also I am using only a 2 pole CPC set and the tube is just sitting bare on top of the PJ so everything is a bit loose. But this is the best results so far.

Some more info on my test Chassis, it has no astig board, and I also did not wire up any astig windings on this set. I also think to really optimize the Frankenyoke and Barkenstien we do need to add the thermal-resistor. It was on the original design for a reason so I think we should add this to the magnet structure somewhere.

One thing i did notice with this set up is that if i over focus, the dots get so big they overlap each other, so there is way to much current than is needed, underfocusing is fine. I think it might be due to the fact I have the dynamics wound too much, 60uh, I think i did this back then because i did not have the right gauge (16) wire to fill the entire 22 mm length of the bobbin and keep the correct 45uh inductance, I used 24 IIRC and it covered one layer but came out to 60uh which i think is causing some adjusting issues. But so far it looks promising. I need to get another set of 6 pole magnets and put the Astig amp board and wire up the Astigs on these barkenstiens. I am not sure if those windings will work. I think they are only 56uh or 60uh i can not remember but the marquees are 156uh. But for those who use the Sony Coils they are 53uh so I am wondering how they work for you guys as i never tested the astig coil yet.

I also have to reopen this Coil up and make sure the Dynamic come after the Static winding so it matches the placement of the Thompson coil, where the beam passes through the Static winding then through the Dynamic. Id like to keep this the same as well.

Athanasios

[dvh99]

thats a nice project with those yokes.
do you wind those coils yourself or do you have someone doing that for you?
and 16 gauge is that the diameter of the thread?
i know that there are transformers with silver windings.
maybe this is something to try on the focus yokes, it might lower the inductance.

[Nashou66]

[dvh99]

wow i am waiting in anticipation.
i saw myself getting a device like nashou has to get the same inductance.
then the question would be what threaddiameter to use 1mm 0.9mm.
smaller diameter is higher resistance.

now to i have to find some frankenyokes.
i understood they were only used in sony1292
any other models they might be in?

[mp20748]

Barco 909 focus coils are better than the 1292's. I have a set in my Marquee now. I once had a set of 1292 coils, but did not like them.

The 909 coils have a more precise focus range and are easier to work with. Unlike the 1292 coils, they are closer to the design for that type of tube used in the Marquee.


But of course, that's if you can also find them.

[cmjohnson]

Once I've successfully completed my experiments, I will be able to convert most any of the K-D brand yokes to be optimized for Marquees. Ideal resistance and inductance values, ideal magnetic strength.

I'm collecting the parts I need to build my magnetizing jig right now. I'm a few capacitors short of what I need. But I already have all
the hard to find parts, the massive toroidal transformer to rewind as a single coil being prime among them.

I guess anybody with enough patience could rewind their own coils, but to change the magnetic field strength of the magnets in the coils
to the optimal value requires special equipment. I'm making the investment in that equipment.



CJ

[Nashou66]

Like I said earlier in the thread the Barco yokes have the same if not better Static focus ability as the Stock Marquee Thompson yoke when not connected electronically.
Mike can also attest to this, however his 909 coils seem to have the same coil values or close to those of the Marquee's. Id like at least one here for testing,measuring, etc.

The 1292 magnet structure would definitely benefit from an increase in magnetization as would older weaker magnet structures.

The only way to know for sure how strong the static focus is to unplug your yokes. If its fairly well focused then you do not need them magnetized any more.


Athanasios

[dvh99]

so now i am on the lookout for 909 coils thanks mike.
where to find this needle in a haystack . ehm 3 needles
i will send a mail to arbey the barco guy.
can pick them up personally if he has some.
i will mail barco too they might have some lying around.
i hope they switched to digital alltogether and want to get rid of their obsolete stuff taking up space. just kidding i dont like digital.

i will mail a company here in holland that makes very high quality trafos and ask them how to achieve a certain magnetic field strength, i will report that here once i got an answer.

[cmjohnson]

Just a thought here...wait until I've done my prototypes and announced complete success. Then, at that time I can use most ANY K-D yokes and turn them into optimal yokes for Marquees. Rewind and remagnetize them to the IDEAL values. 909 yokes are very hard to
find, and justifiably so. But less desirable types built on the same basic design are completely suitable for conversion. When I'm done,
it won't matter if the donor yokes are from a 909 or a Sony 1292 or an AmPro or some other PJ....it's the after conversion results that
matter, and at that point they should ALL be the same.

CJ

[Nashou66]

[cmjohnson]

I think I need to add that I have learned that there are SOME models of K-D focus yokes which are not useful for Marquee usage no matter what you do to them as their core diameter is simply way too small. They are suitable for thin necked Toshiba tubes, as found in, for
example, NEC XG 75s, but in no way, shape, or form are they going to be any use at all for a Marquee.


One part number for one of these useless yokes is KQD17. Don't bother to save up any K-D yokes which have the small diameter central hole.

The ones that are suitable have a hole diameter of about an inch and a half. The useless small ones have a hole diameter under an inch and a quarter.


CJ

[dvh99]

oh my god when will u use the metric system i had to get those silly measurements allen tools 3/16 9/64 lol.
inches and fahrenheit so funny.

[cmjohnson]

It's deeply entrenched in American culture and you'd better get used to it. Why did you Europeans feel the need to mess with a perfectly
sound system?

I'm not handicapped and unable to work in metric, though. I convert to metric in my head when needed.

Say 30 mm for the small hole in the KQD17s, and 38mm for the larger hole in the KD yokes that are usable for the conversion. That's close enough.

Don't criticize my love of the Imperial standards system or I'll double the price on the Advanced FrankenYokes, just for you!

[Nashou66]

Here is a pic from my first Barkenstein yoke I have been testing.



I found I got better focus this time by moving the coil back and forth till it focus
well at settings i had the other two tubes with stock coils at, it cam out to be about
9mm behind the convergence yoke, or where the stock coils is. the edges where i thought i had trouble with came in nicer.

But I am still going to do a new wind of the Dynamic with 16 gauge and the static with 30 gauge.

But as they are now they are ready for use in my opinion.


One more thing that might be affecting my specific set up is i am using a deflection coil from
an 8 inch tube, I think i asked this before but are the 9 inch coils much different in shape
so they would fit better on the 9 inch bell housing?

If any one has some 9 inch deflection coils let me know.

Athanasios

[cmjohnson]

What is your static focus value?

Don't work on this too fast...I'm supposed to be the guy who leads in the Frankenyoke project! Slow down a bit!



CJ

[Sparky015]

Sort of related, but I was doing a search for the heck of it looking for 9 inch tubes. I figure as My 8 inch tubes age, I would look for some 9 inch, preferrably LUGS, at a decent price for a future upgrade. In my quest, I found this website:

www.tubularoutlet.com/index.html

Not sure if any of you have any experience with these guys as you work on the frankenyoke project?

Paul

[Nashou66]

[Nashou66]

[cmjohnson]

I mean, what's your static focus value in the Marquee's focus setting? With 50 being ideal, how close are you?

I'm just pulling your leg about being first. It doesn't matter!




CJ