The Szmaragd 901 OT 1791 black-and-white television set is one of the development variants of TV models of the same name. Three versions of the receiver were made by the Warszawskie Zakłady Telewizyjne: Szmaragd in 1959, Szmaragd 901 two years later (its production ended in 1964), and soon after that – the Szmaragd 902 OT 1711 variant, whose systems were based on printed circuit boards. The Szmaragd 901 allows the reception of 10 television channels (even though only one channel was available in Poland up until 1970). Numerous modifications and corrections were introduced to the original model, which improved the operation of the device. Some structural parts and electrical components were changed. The Szmaragd was developed at the same time as the Turkus and Jantar television sets, hence it shares similar design solutions with them. Although the models and their variants differ from each other, they were developed using parts and components used in the design of the first Polish television receiver, the Belweder.
The modernised Szmaragd model 901 was equipped with a 12-channel switch and a 17-inch CRT. Contrast and brightness adjustment using a remote control was also introduced. In terms of the electrical system, it is a superheterodyne with 17 vacuum tubes, powered with alternating current from the mains and with a built-in magnetoelectric speaker. The design uses a cathode-ray tube with a deflection angle of 90°, which allowed the device to have shallower housing than the previous model.
The break of 1950s and 1960s saw the beginning of a rapid growth of television in Poland. At the beginning of the 1960s, television programmes, hitherto broadcast in different forms by independent regional stations, became centralised. Even though in the early 1960s the number of subscription fee payers was on a par with the number of television sets, there were several times more television viewers than actual television sets. In those days, television was watched together with other household members, often also with neighbours or more distant family. The scale of that phenomenon, as well as the growing demand for TV sets, was demonstrated by the fact that during that period, the number of television subscribers increased by between 300,000 and 400,000 per year. At the beginning of 1960 it was only 426,000 but had reached a level of almost 1.7 million by 1964.

Authors: Piotr Turowski, Filip Wróblewski