01-28-2023, 07:47 AM
The picture tube in the first picture looks like it's spherical faced, which is common with rectangular picture tubes from the mid 50s onward. What you are thinking of are cylindrical faced picture tubes, some of the most common TVs featuring those are Sony Trinitron sets. However the number you gave, 21EP4, according to my G.E tube manual, are you sure that is correct?