On 13th 1831 James Clerk was born into the family of a lawyer Maxwell, it happened in a Scottish town called Glenair. James received his secondary education in Edinburgh Then he studied at the University of Edinburgh and later at the university of Cambridge too. In 1865 he suffered a serious disease and “retired”. In those times his ingenious works arose. Maxwell predicted with his calculations, that from the point of an electric shock (e.g. a sparkle oscillatory discharge) the electromagnetic waves had to spread into all directions. These waves are in fact identical with the light waves and therefore they spread as quickly as the light. But Maxwell had no idea what his mathematic formula might mean for mankind. In those times he didn’t find much understanding for his work and he himself was not a great experimentalist and couldn’t therefore prove his truth. He also didn’t have much time. When he died he was 48 years old.

7 years after his death a person appeared, he made a point of proving this couple of equations. The name of this bold fellow was Heinrich Rudolf Hertz. “It there are some electromagnetic waves”, he said, “they have to behave as the solar or sonic waves. Why not to throw them upon a mirror. Then it will be possible to observe, whether they will rebound or not.” Well, this is easy to say, but difficult to do. Hertz was helpless for a long time. But then he awoke to a fact, that a tuning fork resounds only such string of the piano which is tuned to the agreeing tone. Moreover, if the tone lay out of the piano’s volume no string would be resounded. Hertz took in, that he must “tune” the waves to such a “sound”, which he can prove, only then can demonstrate the existence of electromagnetic waves. All the actual waves were a few kilometres long.

Because Hertz knew Thompson’s formula, he knew, that the length of the electromagnetic waves depends on the shape and the length of conductors (on the capacity of a condenser and on the inductance). He took 2 straight, 40 cm long copper bars and he fixed them so that they were in one straight line. The bars were isolated. Distance between the two bars was 5 mm. So he actually made a dipole antenna (similar to the one we know from television transmitters). After connecting this circuit with an inductor, an electric sparkle skipped over between the two dipoles. To prove the existence of an electromagnetic wave he winded up a wire, its ends made an imperceptible spark gap. So he made an electromagnetic resonator. When the resonator was in good position he could see, with the help of a magnifying lens, a tiny sparks in the spark gap. We could say, that at this moment a wireless telegraphy, radio and television were born. But a lot of time passed before this sparkle conquered the world…

In those times a professor of physics Alexander Stepanovic Popov worked at a Military school in Kronstadt. He was known to be interested in lightnings and sparks and therefore he was asked to make a storm registrator for a Petrograd meteorological station. It turned up, that Popov´s “lightning machine” did not respond well only to the natural lightning, but also to man-made short and long – dots and marcons. On 7th May 1895 Popov demonstrated his apparatus to the members of the Russian physical and technical society: a lightning conductor as an antenna, cohere, telegraph relay and a bell. This was the first telegraph station in the world, which could work without any wires. In December in the same year he announced being a success with regular connection and On 21st March 1896 at the Petrograd university, he demonstrated it in public. He realized this demonstration between two buildings, which were 250 far from each other. For his experiment he chose a symbolic despatch:

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G E N R I CH  G E R C (Henrich Hertz)

Popov´s receiver

When the 36-year-old Popov demonstrated his storm registrator for the first time, under the Italian azure sky a 21-year-old man was doing simmilar experiments with electromagnetic waves. This Italian had some Irish blood in his veins (after his mother’s father) and his name was Guglielmo Marchese Marconi. His experiments with Hertz’s antenna brought him to a conclusion, that only a half of this antenna is necessary for transmitting in case the other part of the spark gap in the transmitter and the cohere in the receiver are well earthed. This vertical Ctvrtvlnný homopole is still used under the name Marconi´s antenna. After he succeeded in telegraphing over the distance of 3 km, he didn’t hesitate and offered his spark station to the Italian government: but the expected enthusiastic reception didn’t take place The Anglo-Saxon part of his blood didn’t bear this injustice and so the second act of his career came about in England. There, on 2nd October 1896 he registered his apparatus for patenting. A year later he broke through the distance of 5 km and then he received a patent for his wireless telegraphy set.

Popov hadn’t originally his invention patented. First in February 1900 he received a patent No. 2797 for “Coherer’s Improvement For The Telegraph Signalisation”. He didn’t meet with full recognition. Marconi was more lucky: in 1909 he won the Nobel prize and after the world war one he was elected Italian senator, he also became doctor honoris causa at many Universities.

To be continued