Convergence ?

[Alex KL-1]

Originally Posted by Electronic M

There are things you can do. First thing I would try is using an external service degaussing coil to try and get the impurity to go away, then if it doesn't I would go through the purity adjustments and see if I could adjust it out. (Edge purity is highly dependent on deflection yoke position so doing a full by the book purity may fix it). If that doesn't fix purity maybe try a refrigerator magnet on the bell near the bad spot as a last ditch.

EDIT: to keep from going off topic others mentioned some sets are a pain to converge... I've found 2 things influence that bad convergence board parts (R,C and diodes), and convergence yoke placement and warping. Sometimes the yoke needs to be back or forward ~1/4" from where it's at to either have more range or overshot less, I've also seen some plastic yokes where one set of petals is angularly closer than it should be due to plastic degradation... That's not easy to deal with.
What probably gave me my worst headaches until I realized was a 19" metal cabinet Zenith a respondent to this thread sold me a while ago...I spent a bunch of time troubleshooting the board because of top hat diodes that looked like they'd been soldered in by Ray Charles, then finally realized that the convergence yoke was installed BACKWARDS and the red yoke petal was over the green gun and vice versa....It got really good when I fixed that.

Great, thanks! So there is some hope.

Too bad, the service for this model have the complete setup only for the in-line CRT (at least indicates the preferred sequence for the convergence board adjustments), so I need to apply/use the "generic" delta gun alignment then... What is the most preferred documentation for learning that (if extra degaussing not solve the problem)?

About EDIT: inspired by the simple "Convergence?" thread title, I ended posting about it just here... ;-) but if moderators prefer to change this postings to a independent thread, I'm also happy :-)