Blue pulse shaping circuits

[old_tv_nut]

Don't know what you mean by "equalize the waveforms on both sides of the coil."

The purpose of the second harmonic circuit is to add a ripple to the vertical deflection of the blue beam. The basic blue dynamic convergence waveform for a round tube has two parts: a sawtooth that makes a difference from left to right, and a first harmonic parabola that makes both edges different from the center. On a rectangular tube, the second harmonic is added, to make a difference between (center and edges) and (halfway between center and edges). In other words, without the second harmonic, you could have both the center and the left and right edges converged, but the left-center and right-center would be off. Or you could have the center and most of the width OK, but the extreme left and right would be off.

If the second harmonic circuit is way off (coil broken), it will not produce symmetrical effects at left-center and right center, because it may introduce less second harmonic, or introduce some first haormonic, or who knows what.

If you are now getting acceptable blue convergence all the way across from left to right, you have found the right adjustments.