zenith porthole question

[John Marinello]

Has this set been restored? If not, then you should be thinking full restoration, and not of repairing the set. If you insist on operating the set as-is, keep close
tabs on the four filter cans. If any start getting hot, you had better shut it down in a hurry. Also, there is a picture control switch in the pencil box. You
need to have it in full circle mode before you can make height + linearity adjustments. Looks more like the AGC is set too high. Do you need a channel knob for it?