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What will be shown first will be a very, very brief history (mostly
last names and dates) which will show when some of the discoveries were
made which made radio communication possible. In the second part will
be shown some of the activities by ham operators which has shaped the
history of radio. This will be just a sketch. Many of you probably know
much more than I about the subject. These pages are directed, however,
toward those whose knowledge is limited. I think the study of radio
history is very interesting.
People who invented gadgets which made radio communications possible:
Probably from the time man learned to make a sound he has attempted to send his thoughts and ideas over ever increasing distances.
Early man found that he could increase the distance he could communicate by using drums and mallets. In some less developed parts of the world humans still use the drum to send messages.
As technology evolved man has used fire, crude lanterns, mirror devices, and other methods to signal greater distances than would have been possible by voice alone.
All the methods shown above fall short. They are effective only over comparatively short distances.
There have been many people who have been responsible for radio communication as we know it today.
Charles Coulomb discovered the basic laws of electricity in the eighteenth century.
In 1779 Alessandro Volta invented the "voltaic pile". It was the first battery and was made by leafing alternate plates of copper and zinc seperated by cloth discs. Later someone came up with the idea of using sulfuric acid which improved the performance.
In 1600 a Dr. Gilbert disproved the theory to date regarding interaction of electrical and magnetic poles.
In 1820 Oersted discovered that electric current in a wire will deflect a compass needle.
In 1876 Rowland charged a vulcanite disc and rotated it at high speed near a compass. The needle was deflected.
Oersted's discovery caused Andre Ampere in 1810 to recoginize how an electro-magnet could be used for communications and hinted that an electric telegraph was possible.
Actual construction of a telegraph device was made by Samuel Morse in 1844.
In 1828 George Simon Ohm announced that he had come up with a formula which would make it possible to measure electrical properties. The formula is still in use today and known as ohm's law. It is I=E/R. From that time forward those who were prone to tinker could speak a common universal language.
In 1821 Faraday invented the electric motor in the form of the "Faraday Disc".
In 1843 Robert Kirchoff took into account Ohm's law and announced two famous formulas.(1) the algebraic sum of all voltages drops around a circuit is equal to zero. (2) The sum of the currents entering a junction is equal to the sum of currents leaving the junction.
In 1831 Faraday disclosed the principle of the transformer.
In 1851 Ruhmkorff invented the induction coil.
In 1746 a Professor Mussenbroek invented the first capacitor.(a glass jar with an outer and inner layer of foil. He called it the" leyden" jar.
Before Morse invented the electric telegraph others tried communicating by the conductivity method. In 1811 Somerring communicated across a river in Munich. Steinheil placed electrodes in the ground and worked about 50 feet in Bavaria in 1838. Preece worked a distance of 5 miles or so across the Bristol channel in 1892.The conductivity method is no longer defined as wireless. Radio communication is one which employs electro-magnetic waves which were not understood at the time of the tests shown above.
James Clerk Maxwell organized the knowledge generated by Oersted, Ampere, Volta, and Faraday and created a unified group of related formulas. All wireless communication as we understand the term today is based on Maxwell's equations. In 1887 Heinrich Hertz succeeded with an apparatus using sparkgap in bringing in a new era where wireless was at last possible.
Other people added to the knowledge: Lodge, Branley, Marconi, Schloemilch, Pickard, Poulsen, Duddell, Fleming, DeForest, as well as countless other "amateurs" who were taken up with the idea of wireless communications. The age of wireless communications was born and the world would never be the same again.