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More astonishing still is the fact that in 1893； two years before
Marconi demonstrated his system of wireless signaling； Tesla had built a
model boat in which he combined power to drive it with radio control and
robotics。 He put the small boat in a lake in Madison Square Gardens in
New York。 Standing on the shore with a control box； he invited onlookers
to suggest movements。 He was able to make the boat go forwards and
backwards and round in circles。 We all know how model cars and aircraft
are controlled by radio today； but when Tesla did it a century ago the
motor car had not been invented； and the only method by which man could
cover long distances was on horseback！
Many people believe that a modification of Tesla's ‘Magnifying
Transmitter' was used by the Soviet Union when suddenly one day in
October 1976 they produced an amazing noise which blotted out all radio
transmissions between 6 and 20 MHz。 （The Woodpecker） The B。B。C。； the
N。B。C。 and most broadcasting and telecommunication organisations of the
world complained to Moscow （the noise had persisted continuously for 10
hours on the first day）； but all the Russians would say in reply was that
they were carrying out an experiment。 At first nobody seemed to know
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
what they were doing because it was obviously not intended as another
form of jamming of foreign broadcasts； an old Russian custom as we all
know。
It is believed that in the pursuit of his life's ambition to send power
through the earth without the use of wires； Tesla had achieved a small
measure of success at E。L。F。 （extremely low frequencies） of the order of 7
to 12 Hz。 These frequencies are at present used by the military for
communicating with submarines submerged in the oceans of the world。
Tesla's career and private life have remained something of a mystery。
He lived alone and shunned public life。 He never read any of his papers
before academic institutions； though he was friendly with some journalists
who wrote sensational stories about him。 They said he was terrified of
microbes and that when he ate out at a restaurant he would ask for a
number of clean napkins to wipe the cutlery and the glasses he drank out
of。 For the last 20 years of his life until he died during World War II in
1943 he lived the life of a semi…recluse； with a pigeon as his only
companion。 A disastrous fire had destroyed his workshops and many of his
experimental models and all his papers were lost for ever。
Tesla had moved to Colorado Springs where he built his largest ever
coil which was 52 feet in diameter。 He studied all the different forms of
lightning in his unsuccessful quest for the transmission of power without
wires。
In Yugoslavia； Tesla is a national hero and a well…equipped museum
in Belgrade contains abundant proof of the genius of this extraordinary
man。
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
CHAPTER TWO
THE BIRTH OF RADIO COMMUNICATIONS
By 1850 most of the basic electrical phenomena had been
investigated。 However； James Clerk Maxwell （1831…1879）； Professor of
Experimental Physics at Cambridge then came up with something entirely
new。 By some elegant mathematics he had shown the probable existence
of electromagnetic waves of radiation。 But it was twenty four years later
（eight years after Maxwell's death） that Heinrich Hertz （1857…1894） in
Germany gave a practical demonstration of the accuracy of this theory。 He
generated and detected electromagnetic waves across the length of his
laboratory on a wavelength of approximately one metre。 His own
photograph of the equipment he had set up can be seen in the Deutsches
Museum in Munich。
To detect the electromagnetic waves Hertz employed a simple form
of oscillator； which he termed a resonator。 But it was not sensitive enough
to detect waves at any great distance。 Before wireless telegraphy could
become practicable； a more delicate detector was necessary。
Credit is due to Edouard Branly （1844…1940） of France for producing
the first practical instrument for detecting Hertzian waves； the coherer。 It
consisted of two metal cylinders with leads attached； fitted tightly into the
interior of a glass tube containing iron or steel filings。 The instant an
electric discharge of any sort occurred the coherer became conductive； and
if it was tapped lightly its conducting property was immediately destroyed。
In practice the tapping was done automatically by a tapper which came
into action the moment the coherer became conductive。
In Russia the physicist Aleksandr Popov （1859…1905） had used a
coherer while engaged in the investigation of the effects of lightning
discharges。 He suggested that such discharges could possibly be used for
signaling over long distances。 Old timers may remember that about 50
years ago Russian amateurs used to send out a QSL card with a drawing of
Popov and a caption which claimed that he was 'the inventor of radio'。
In Italy； a young 22…year…old electrician became interested in
electromagnetic radiation after reading papers by Professor Augusto Righi
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The dawn of amateur radio in the U。K。 and Greece ： a personal view
（1850…1921）。 It was Guglielmo Marconi （1874…1937）； the son of a well…to…
do landowner who lived in Bologna； and who was married to Annie
Jameson of the well known Irish Whiskey family。 Guglielmo； their second
son； had his early education at a private school in Bedford； England； and
later at Livorno and Florence in Italy。 When he read about the experiments
of Heinrich Hertz and about Popov's suggestion； he saw the possibility of
using these waves as a means of signaling。 His first transmitter； shown in
the accompanying photograph； did not radiate very far。 When he folded
the metal plate into a cylinder and placed it on a pole 30 feet above the
induction coil and connected to it by a vertical wire； he was able to detect