Q: The corresponding relationship between bifocal line and focusing knob and focusing electrode.

Several different dual-focus high-voltage packages were observed. It is found that from the leading position of the focus line on the focus box, which adjustment knob can be used to control a focus line can be determined. Several high-voltage packages are marked with FOCUS 1 on the upper adjustment knob and with FOCUS 2 on the lower adjustment knob. It is found that in some high-voltage packages, the red focus line is drawn from the lower part of the focus frame near focus 2, and the white focus line is drawn from the upper part of the focus frame near focus 1. But some high-voltage packages are just the opposite. It can be seen that it is uncertain whether the two adjustment knobs of FOCUS 1 or FOCUS 2 control the red line or the white line for different dual-focus high-voltage packages. What I want to know now is: which of the two focusing lines, FOCUS 1 and FOCUS 2, is connected to the dynamic focusing coupling capacitor of the high voltage package? In the design, they should be connected to which focusing electrode of the picture tube. For example, the tail plate of the picture tube is facing us and the two focusing electrodes are below, so how do the two focusing lines correspond to the left and right focusing electrodes? []