November 1953 Radio-Electronics
[Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Electronics,
published 1930-1988. All copyrights hereby acknowledged.
Rauland (aka Rauland-Borg)
has today on its History webpage that it was founded in 1922 as the Rauland
Company, by inventor and radio enthusiast E. Norman Rauland. Soon thereafter he
became a pioneer in the radio broadcast industry by launching the Chicago-based
radio station, WENR (which eventually became the well-known
WLS). In 1941 Norm Rauland
and George Borg entered a partnership, and a year later acquired Baird
Television of America. Rauland developed cathode ray tubes (CRT) and became an
important supplier of communications and radar equipment during WWII. After the
war, Rauland began manufacturing CRTs for 10" and 12" televisions. They were so
successful that in 1948,
Zenith Radio Corporation purchased them to get the CRT technology. This
circa 1953 Rauland advertisement ran in Radio-Electronics magazine to pitch
their breakthrough aluminizing process that produced CRTs with brighter pictures
and greater contrast with relatively low anode voltages, which was a big deal at
the time due to concern over high levels of x-rays being emitted. In the 1960s,
newfangled color television sets experienced a rebirth of the problem as beam
currents were even higher.
See The Color
TV X-Ray Problem, and
TV X-Rays, TV X-Rays Are Back,
Whap - You're X-Rayed.
Rauland Zenith Aluminizing Ad
What Aluminizing means
Aluminizing means the efficient use of light - light is energy - energy is the
Aluminizing means a brighter TV picture, greater contrast, lower beam current,
smaller spot size, sharper focus, reduced screen scorch - all from the efficient
use of light.
On the inside of any TV tube face is a coating of phosphor crystals - the picture
screen. As the electron beam - tracing the picture - strikes these crystals, they
glow, giving off light in all directions. And there's the problem! Half the light
thus generated inside the tube, either lost to usefulness or lighting areas that
should be dark. Both brightness and contrast suffer.
But- put a mirror behind the phosphor and "wandering" light is reflected back
through the tube face. Aluminizing creates this desired mirror!
To aluminize a picture tube, deposit a nitrocellulose film evenly over the phosphor.
Over that, deposit a film of aluminum only millionths of an inch thick - just thick
enough to reflect the light and just thin enough to let the electrons pass through.
Under heat, evaporate the nitrocellulose film to leave a think smooth coating of
aluminum. Result - an efficient light reflecting mirror to specifications.
Simple as it sound, Rauland research engineers worked for three years to solve
the problem and were among the first to do so.
Perfection through Research
Posted October 1, 2020