1928 in the Soviet Union

The theremin (; originally known as the ætherphone, etherphone, thereminophone or termenvox/thereminvox) is an electronic musical instrument controlled without physical contact by the performer (who is known as a thereminist). It is named after its inventor, Leon Theremin, who patented the device in 1928.

major centralised economic plan in the USSR

Soviet show trial

radical change in the economic policy of the Soviet Union in 1928/1929