February 1947 Popular Science
[Table of Contents]
Wax nostalgic about and learn from the history of early
electronics. See articles from
Popular
Science, published 1872-2021. All copyrights hereby acknowledged.
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When you see an article
title such as this one from at 1947 issue of Popular Science magazine titled
"Electronic Color Television is Here," you might think well duh, what other kind
of TV would there be other than "electronic?" If you had been around at the time
and were aware of developments in color television, you would know that there were
a couple variations of electromechanical systems being considered. In fact,
RCA and CBS had a rotating color wheel (red, green, and blue segments) which
rotated in front of the video detector tube to separate colors for comprising the
composite signal, and then a similar setup for projecting onto a display screen.
Fortunately, the all-electronic
NTSC format won the competition. Even so, because of complexity and reliability
concerns, the color TV cameras that flew on Apollo 10 and Apollo 11 (the first moon
landing) in 1969 used the color wheel approach. The RCA scheme reported here uses
stationary mirrors, which went away before the NTSC standard became law.
Electronic Color Television Is Here
All-Electronic color television, which RCA
engineers have achieved in a form that does not make black-and-white equipment obsolete,
is a complete departure from the mechanical color transmissions of recent years.
Mirrors and photoelectric cells replace moving parts.
In a recent demonstration at Princeton, N. J., pictures were broadcast with a
new color-slide camera. Its developers plan laboratory transmission of live-action
studio scenes by mid-1947, outdoor action scenes late in 1947, theater-size pictures
in 1948:
The electronic system's mirrors and tubes split a beam of light into red, blue,
and green images. Three kinescopes in the receiver pick up the separate images simultaneously
- in contrast to mechanical systems in which a rotating filter transmits the three
colors one at a time - and project a merged, flickerless picture.
Color television requires much higher frequencies than black-and-white work because
a wider band must be used. The operating standards, however, such as the scanning
rate, number of lines, and rate of picture repetition (30 per second), are the same
as in commercial television. So a frequency converter would suffice to equip any
black-and-white receiver to handle color broadcasts in black and white. Thus the
advent of commercial color television - still some years away by RCA estimates -
need not make present sets obsolete.
Color and Monochrome (B&W) Television
Articles
Posted November 17, 2023
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