Convergence wizards -- How does one really do it after yoke swap?

[Pac-Fan]

Yep, first of all, I've read the K4600 and G07 manuals with their (slightly different but essentially the same) convergence guides.   I tried a K4600 a while back and never got it done right, and now tried a G07 with pretty much the same results.

The problem is that if I get the middle and one vertical half aligned right (vertical with respect to 4:3 orientation, so the upper or lower half of a 'normal' TV screen), then the other half is out of convergence.

Using crosshatch or dots, I get one half with purple/green fringing if the other is white, or red fringing if the purple is moved back to white.   Tilting the yoke a bit will correct one side but then make the other bad. Combining with moving the convergence rings does the same (They will make the sides 'swap' the misconvergence while keeping the center in convergence when moved just a small amount). It's almost like I need the yoke to "fold" to push both sides inward a bit, not one side causing the other to pull away.

The yokes came off tubes that were in convergence but had lots of burn in and weak guns. They were transplanted on very good TV tubes that were in convergence themselves with their tv yokes when tested with a replacement chassis before pulling off the TV yokes and putting the arcade monitor yokes on.  (The TV yokes were not wide enough for use producing a square image, plus I'd rather keep the G07/K4600 up and running on good tubes.) The convergence rings were marked and replaced on the tube they were on. and put back exactly where they were.

Static convergence is easy with the rings.  I realize dynamic convergence is hard, but I'm 0 for 2.. I just can't live with Purple + Green dots on half of the Ms.Pacman game screen or Blue/purple high score lists in QBert due to the bad convergence

Has anyone really gotten it as good as the original tube the yokes were on after swapping? Is there a trick to making it easier?  Is there inheritent incompatabilities with yokes and certain tubes?

[grantspain]

firstly it is important that the yoke is correctly positioned i.e on the rubber butt's
you need to use a grid not cross hatch or dots,here http://www.lynxxx.nl/barco/patterns/
start with the green,once you get that 100% then continue with red,then blue individually over the perfect green grid
disconnect the colour signals that you are not using so you don't get confused
note the function of each yoke adjustment ring

[Pac-Fan]

Grid/Crosshatch.. same thing, diff name. That's what I'm using.

Yes, I cut the appropriate guns.  I tried the steps in G07, K4600 and even the Disco manual (all essentially the same), and all met with very unsatisfactory results on a 19" tube.

I even threw a 13" tube in with a G07 13" yoke connected to a 19" g07 chassis, and got near perfect convergence on it the first try. But the throw of the yoke is so much less than on a 19", so it's virtually impossible to do a 19" that easily.

As a test, after giving up, I pulled the rubber yoke stops off the original g07 tube that was burned in (but worked), then reset the convergence rings to a random starting point.  Within 5 minutes I had the original tube realigned as well as it was before I started.

This leads me to believe that, contrary to popular belief/numerous web sites touting it, you can't just pull a random TV tube, swap a classic arcade yoke on it and have it work like new.  Even though both tubes were type 23 pinouts, both were 90 degree deflection, they just were not the same compatability.  If I hadn't been able to reconverge the original tube after swapping, I'd know I had done something wrong, but since I did, I can only believe it's an incompatability with tubes.

Definitely not worth the time to try unless you know in advance a particular tube type will work.  Much better to just order the replacement chassis and slap it on a TV tube and have a working set in 5 minutes of work instead of a few hours and still not working.  It's sad to not be able to bring the classic chassis back with a good clean tube though.

[grantspain]

there certainly is a compatibility problem with some tubes and yokes,its not a case of any yoke will fit any tube
sounds like you know what your doing so after messing for hours and not getting a result it is def time to give up and spend some money