CT-100 as shipped from RCA

[old_tv_nut]

Originally Posted by julianburke

A color CRT does have some issues with the earth's magnetic field but nothing that can't be solved with a tech with experience. However, I have never heard of and never experienced any problems with that issue with any color camera. That's a (technicians') wives tale. A properly set up TK41 delivered great color in any position. For that matter, if it were true it would also bother B&W cameras because they used the same basic circuits, pickup tubes and magnetism doesn't bother the color dichroic lens assembly.

The image orthicons are mounted in a metal tube, which I'd guess acts as a magnetic shield, sufficient for protection from the Earth's field, but not necessarily from man-made fields. The Ed Sullivan theater in NY backed up to a subway transformer station (maybe still does) which caused problems if cameras were too close to the back wall. This was still the case in the early 90s when we shot the first US HDTV tests there on tube cameras (Saticons). Don't know if the substation is still there, but CCD cameras make it a moot point for the Letterman show that is staged there.