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April 1966 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.
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In the mid 1960s, Radio-Craft
magazine ran a series of articles on "Inventors of Radio." This April 1966 issue
featured Boris Lvovitch Rosing (1869–1933), a Russia-born physicist and pioneer
of television technology. Rosing was born in St. Petersburg, where he studied
under Heinrich Friedrich Emil
Lenz and later taught at the Technological Institute. Beginning in 1902, he
experimented with cathode-ray tubes for image transmission, developing the first
electronic television device by 1907, which used rotating drums and a modulated
electron beam to produce images. His breakthrough came in 1911 when he successfully
displayed simple images, earning him recognition and awards. Despite interruptions
from World War I and the Russian Revolution, Rosing continued refining his designs,
achieving higher-resolution scans by the 1920s. However, his work was cut short
when he was arrested during Stalin's purges in 1931 and exiled to Arkhangelsk, where
he died in 1933 from a cerebral hemorrhage.
Inventors of Radio: Boris Rosing
 At the beginning of this century, all the necessary
elements for television were at the disposal of scientists. Karl F. Braun perfected
the Crookes tube in 1897. The great English savant, J. Thomson, introduced deflection
plates. In 1899, the German E. Vichert showed that one could concentrate electron
beams with a winding concentric to the axis of the tube. And finally in 1902 the
Russian A. A. Petrovski suggested that two windings at right angles to each other
could be used for deflection. Scanning with mirrors had also been proposed.
Boris Lvovitch Rosing was born on the 23rd of April, 1869, in St. Petersburg.
In 1887 he entered the Department of Physics and Mathematics of the University of
St. Petersburg, where he was a student of F. F. Petrouchevski, himself a student
of Lenz. At his graduation he was invited to remain as assistant to the Chair of
Physics. Later he worked in physics at the Technological Institute of St. Petersburg.
This placed excellently equipped laboratories at his disposition. In 1897 he became
the director of the physics department there, where he worked until 1917.
Boris Lvovitch Rosing, 1869-1933
Rosing's researches included work on the telescope, on the "photography" of sound,
equipment intended for the blind, a motion-picture projector and a transformer for
direct current. Thus he was led to the study of what he called "electric telescoping."
At the International Congress of Electrotechnique in Paris in 1900, he presented
a report entitled "The Present Position of the Problem of Television." It appears
that this was the first use of the word "television."
In 1902 Rosing started experimenting with a cathode-ray tube for the transmission
of images, beginning with a writing technique in which simple designs and letters
could be traced on the face of the tube.
Rosing's transmitter. Much is unclear, but one drum and sync coils can be
seen.
In 1907 he developed the first electronic television device, using two drums
with mirror surfaces, mounted with their axes perpendicular to each other (Fig.
1). The light from the image fell first on the horizontal drum, which turned at
a speed of 50 revolutions a second. It then went to the vertical drum, which had
a speed of 12 turns per second, and from there to the photoelectric cell. (One of
his patent application drawings showed the light going first to the vertical, then
the horizontal drum.) The current of that cell modulated the strength of an electronic
beam that fell on the fluorescent screen. This was done by deflecting this electronic
stream across a small orifice through a capacitor (pair of deflecting plates), in
such a way that a greater or smaller number of electrons went through the orifice.
In the earliest models the two drums carried potentiometers with sliding arms that
developed sawtooth vertical and horizontal deviation voltages, now supplied electronically.
(Later models used the coils shown in Fig. 1.) These were applied to the vertical
and horizontal deviation windings, which of course were in perfect synchronism with
the transmitter.
This development was patented by Rosing on July 25, 1907, ten years after he
began his first experiment. Rosing applied for and received an English patent in
1908 and a German patent in 1909, and finally, in October 1910, a patent in his
own country.
The first model of the equipment, considerably improved over the original design,
was finished in 1908 in the laboratories of the Technological Institute in St. Petersburg.
A little later he developed the idea of modulating the brightness of the spot by
changing its velocity, and in 1911 applied for a patent covering that idea.
On May 9, 1911, Rosing succeeded for the first time in obtaining an image on
the screen of his rudimentary televiser. It consisted of four white bands on a black
background. The photo at left shows the first transmitter. This success of the "electric
telescope" brought Rosing the gold medal of the Russian Technical Society and several
other honors.
World War I forced Rosing to abandon his experiments and devote himself to work
in connection with national defense. After the Revolution he published numerous
articles, and in 1922 the 25th anniversary of his work in the domain of television
was celebrated. In 1924 the experimental electronic laboratory of Leningrad was
placed at his disposition, and here he developed improved equipment, using a drum
with 48 mirrors for horizontal scan and an oscillating mirror controlled by an eccentric
cam for vertical scan. In this way he was able to produce an image of 2,400 elements.
The time bases were developed with capacitors and resistors, much as is done today.
Finally, the intensity of the beam was modulated by applying the video volt-age
to the cathode.
Fig. 1 - Transmitter-receiver detail.
This activity was interrupted in 1931 when, with many other scientist victims
of the Stalin terror, Rosing was arrested and deported for 3 years into the regions
of the north. Continuing his work under great difficulties, he succeeded in preparing
a number of articles. At Arkhangelsk he was able to use the physics laboratories
of the Forestier Institute, where he continued with his studies. There, on April
20, 1933, at the age of 64, he was struck down by a cerebral hemorrhage.
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