Vitaliy tell us a story about beginning and the First Steps of Russian radio industry

Vitaly Brousnikin, vitalybr@onego.ru

http://oldradio.onego.ru/ 

July 28, 1924 can be considered as the starting point of production of home receiving devices in the USSR. On that day The Soviet of People's Commissars (The Government) of the USSR passed a decree "On private receiving radio stations", which gave the citizens the right to own a radio set. And already in autumn of 1924 the Trust of Low Voltage Factories in Moscow put out the first industrial home radio receiver - "LDV" (Home Detector Broadcasting"). It had a fixed tuning to the wave of the Comintern Radiostation (3200 m). But it did not mean that tuning was no problem. The radio was based on a crystal detector with "an active point". The edge of a steel wire was touching a polycrystal of natural semiconductor. With a small knob the position of the steel pin could be changed.

The crystal DS-4

After some attempts one could "feel" the detecting p-n-transition on the border of the "pin-crystal" and the broadcast was heard in the headphones. No one could move about the room not to "shake off" the active point.

The author has a similar detector at his disposal and tests showed that the ratio of direct and opposite resistance at the active point could reach 1:20. Of course, it is much lower than with a modern diode , but then it was sufficient for detection of signals of powerful local R-stations.

The modifications of radio "LDV" are known as "LDV-2" and "LDV-4". Then followed "LDV-3", "LDV-5" and "LDV-7" - complicated devices with changeable inductivity of the coil in 200-1500 m band. The detector receiver "Proletary" was also very popular.

The first in USSR valve radio was produced at the end of 1924 by the above-mentioned Trust of Low-Voltage Factories. It was the receiving set "Radiolina", consisting of several blocks. The first of them contained a tunable coil with a span of 450-3400 m. The blocks of detector and RF-Audio amplifiers were connected to it.

The first Rrussian vacuum tube was created in 1915 by M.A.Bonch-Brouyevich, a talented engineer, when he was Chief of the military telegraphic receiver in Tver. This tube later nicknamed as the "Babushka" (Grandma) honestly worked in the receiver of telegraphic signals, successfully compete with imported French valves

http://www.antentop.org/

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