Monitor "Focus" Question

[FrizzleFried]

OK...I have an old G07 in a newer tube that looks fantastic.  I also have a G07 chassis in an older tube that is quite a bit less focused that the other (and yes,  it is a focuses as it will get).   Is this a deficiency in the chassis (caps) or the tube itself?

[Grauwulf]

It could be one of several things, but the most likely culprits are a cap kit if it hasn't been done, or the tube itself has a problem and should be put on a tester/rejuvinator. The other thing it could be is the flyback itself, but like I said, I would loot at the other two first.

[Ken Layton]

Overall focus is generally attributed to the tube. Either one color is weaker than the others or the focus section of the tube is having problems. Putting the tube on a rejuvenator (restorer/analyzer) can tell and probably fix it. This is the most common problem and probably applies to your monitor.

Sometimes the focus winding inside the flyback can go weak and not deliver the full focus voltage. The Wells-Gardner k4900 series is well known for that problem.