evision: - Early Television Foundation

2
THE MOVING FINGER WRITES"
EMEMBER those lines from Omar Khayyam?
"The Moving Finger writes; and, having writ,
Moves on: nor all your Piety nor Wit
Shall lure it back to cancel half a line . . ."
That might apply to television; except that
the "moving finger" is a cathode beam made up
of a few million electrons. And our piety and
wit manage to lure it back to cancel five-hundred-and-twenty-five
lines thirty times a second.
In the next few pages, we're going to describe
how television works. This is
important. To
have a clear understanding
of where television
is
going, we must appreciate the technicalities
which will decide ultimately how far it
can go,
and how it can get there. This chapter deals
with some of the most complex theory in mod-
but it's as plain and graphic and
ern electronics ;
non-technical as science can be described.
Chances are you'll get through
it
12
without even