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For television reception, Polevoy (Vekshinsky's laboratory) has
designed two types of tube. One is a small type of tube having a
screen diameter of 120 mm. It is equipped with electrostatic
focusing and magnetic scanning. The diameter of the beam is 0.6-0.8
mm and its current is 150 microamps. The slope of the characteristic
is 8-10 microamps/volt and the ratio of the accelerating field on
the second and first anodes is 5. The other tube is larger and
having a screen diameter of 200mm. The fluorescent screen is
willemite.
Employing the small type of tube, Gourov's laboratory have designed
a commercial 120 line vision receiver having a thyratron scanning
circuit. In construction it has the form of a tall cabinet
subdivided by horizontal partitions into three compartments, one
above the other. The top compartment contains the tube with the
magnetic scanning system, a potentiometer for regulating the depth
of modulation and a rheostat for regulating the brightness of the
picture. In circuits with amplifiers, the dividing stage and the
stage for the suppression of the return path of the beam. The loud
speaker is also accommodated in this compartment. The bottom
compartment is for the rectifiers which are run off the 110 volt AC
mains. A 240 line televisor of the same type is at present
undergoing tests.
(Courtesy of George Lemaster)
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