Postai és Távközlési Múzeumi Alapítvány Évkönyve, 1997

Rövid tartalmi összefoglaló angol nyelven

performance semiconductor transmitters that would improve quality. The domestic development of these was the 5 kW semiconductor range of transmitters launched in 1996.

The other side of broadcasting was television, which developed in Hungary at the end of the 1950s. The Hungarian transmitter industry began experimenting at the same time as the Post’s experiments. The first 1 kW television transmitter began broadcasting at the end of April 1957 from a building on Széchenyi Hill in Budapest, and the second at Kékes in 1960.

Two transmitters were then imported, for Budapest (30 kW) and Szentes (20 kW), after which the Hungarian industry supplied the equipment, transmission apparatus, antenna systems and measuring devices for subsequent stations. One major assignment at the end of the 1960s was to make the first UHF-band transmitter. This was done as part of the development of colour television.

The type of television apparatus to be made in the largest quantities was the one made in the second half of the 1980s. It continued until the arrival of fully semiconductor transmitters.

Ernő Beszédes: Telegraph birthdays

This exhibition marked the 160th anniversary of the invention Samuel Finley Breese Morse presented on September 2,1837, and the 150th anniversary of the installation of Hungary’s first telegraph line, between Vienna and Pozsony (Bratislava) on December 26,1847.

For the first time in communications history, messages were sent in 1837 from one place to another as electric signals travelling at the unimaginable speed of 300,000 km/ sec. The ancestor of the telegraph had been an optical semaphore signalling device invented by the Frenchman Claude Chappé in 1793. At the end of 1794, this was used to send short messages between Paris and Lille in half an hour. The stations were an average of 11.25 km apart, and each signal travelled through 16 stations a minute.

The use of electricity brought a remarkable change in communications. The first electric signalling systems used electromagnetism. The system designed by the American inventor Morse came amidst other attempts by Sömmering (1809), Ritschi (1830), Alexander (1837), Schilling (1837), Cook and Wheatstone (1837) and Bain (1843). As originally demonstrated in September 1837, the Morse system was simple, but difficult to use. It underwent several alterations before reaching its final form.

The US Congress offered $30,000 on March 3, 1843 for the construction of telegraph lines. The first exchange of telegrams took place between Washington and Baltimore on May 27,1844. The Morse telegraph met all the requirements of an electric system in those days, and soon spread all over the world. Within limits, it has remained in use to this day.

The advance of the telegraph continued with the development of the telegraph typewriter. A machine patented in 1855 by David Edward Hughes, a teacher from New York, was adopted for international use, at the International Telegraph Convention in Vienna in 1868. This type also includes the Siemens-Halske letter-printing telegraph demonstrated at the electro-technical exhibition in Frankfurt in 1891.

The time-multiplex principle devised by the Frenchman Baudot in 1874 allowed the lines to be used for several messages at once. This principle led to the arrhythmic, asynchronous telegraph typewriter (1914-18), which are still the most widespread type today.

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