CT-100 mumetal shield removal

[dtvmcdonald]

There was a minor problem shown in these pictures, best seen in the one of
the children bearing leaves and the leftmost B&W intensity step pattern. You
will note that the left half of the screen was a bit reddish. This was clearly
visible with contrast all the way down (which in a CT-100 turns color all the
way down too) and brightness way up. (The background in the Christmas picture
is supposed to be a yellowish off-white.)

It was caused by a modification I made after the first internal arc in the old
CRT. I added 100K resistors in series with each CRT screen grid (G2). These
are used in all the RCA 21AXP22 and 21CYP22 sets to protect against damage
from arcs to or from G2, which is connected to a big fat 80 uF cap.
I did not remove them.

This allowed capacitative pickup from the multi-hundred-volt dynamic focus and
convergence waveforms. It was cured, with no loss to the protective function,
by bypassing the three resistors with 1 kV 1nF ceramic caps.

P.S. .... the children, of course, were back in 1954 wishing for a CT-100,
just like me!