If you turn to a simple layman, he will probably say that the radio is dying, because in the kitchen the radio point has long been cut off, the receiver only works in the country, and in the car your favorite tracks are played from a flash drive or an online playlist. But you and I know that if there were no radio, we would not read on HabrΓ© about space, cellular communications, GPS, television broadcasting, Wi-Fi, experiments with microwaves, smart home and IoT in general. Yes, and there would be no Habr, because the Internet is also radio. Therefore, today, May 7, 2019, we are writing a post of gratitude to the radio, which has done more for the development of society than all the revolutions and intergalactic corporations combined.
The life of the radio is not just the story of some technical entity, it is precisely life: parents did not believe in it and believed that it was capable of small things, it was limited in its capabilities, it was used for evil purposes, it helped to defeat good and save people and it eventually took over the world and became the founder of a separate technological universe. Why not a superhero story!
Broadly speaking, radio is communication using radio waves. It can be one-way, two-way or multilateral, provide information transfer or exchange between machines and people - this is no longer the point. There are two main words here: radio waves and communication.
First of all, let's put an end to the beginning of the article - why May 7? On May 7, 1895, Russian physicist Alexander Stepanovich Popov conducted the first radio communication session. His radiogram consisted of only two words "Heinrich Hertz", thus he paid tribute to the scientist who laid the foundations of the future radio. By the way, the primacy in the radio business is disputed not only by Guglielmo Marconi, who also held the first session in 1895, but also by a number of other physicists: 1890 - Edouard Branly, 1893 - Nikola Tesla, 1894 - Oliver Lodge and Jagadish Chandra Bose. However, everyone made their contribution, and it is worth adding a few more names: James Maxwell, who created the theory of the electromagnetic field, Michael Faraday, who discovered electromagnetic induction, and Reginald Fessenden, who was the first to modulate a radio signal and on December 23, 1900, transmitted speech over 1 mile - with a terrible quality, but it is the sound.
A. Popov and his invention
The first experiments with wireless transmission of information were carried out by Heinrich Hertz. His experience was successful - he was able to convey the message within the same attic of his own house. Actually, this would have been the end of the matter if the Italian Marconi had not read this remarkable fact in Hertz's biography. Marconi studied the issue, combined the ideas of his predecessors and created the first transmitting device, which did not receive interest from the Italian authorities and was patented by a scientist in England. At that time, an electronic telegraph already existed and, according to Marconi, its device would complement the telegraph where there are no wires. However, Marconi's invention was used for communication on warships, and sending messages simultaneously to a large number of listeners remained in the future. Yes, and Marconi himself did not believe in the brilliant future of radio communications.
G. Marconi and his invention
By the way, about the ships, more precisely, about the navy - in 1905, in the Battle of Tsushima, the Japanese fleet defeated the Russian squadron, partly "thanks" to the radio equipment that the Japanese military leaders bought from Marconi. But this was not the last argument in favor of the complete radio coverage of the military and civil fleet. The last word turned out to be another, this time civil, tragedy - the death of the Titanic. After 711 passengers were saved from the sinking giant thanks to radio distress signals, the maritime authorities of the developed countries of the world ordered that every sea and ocean ship had radio communications, and a special person - a radio operator - listened to incoming signals around the clock. Maritime security has increased dramatically.
However, they did not particularly believe in other prospects for radio.
But numerous radio amateurs believed. By World War I, so many amateur radio stations had been created that the governments of the countries were in a panic: amateurs connected to military communication sources and listened to the channels. Therefore, the radio became the object of regulation, and there were no longer those who underestimated it. It became obvious that in the hands of humanity is a powerful cultural phenomenon, an information weapon and a promising technology. Although, we are ready to argue, then no one knew about the true prospects of radio.
However, radio split the life of mankind in the twentieth century into three parts:
November 2, 1920 - First US commercial radio station, KDKA, goes on the air in Pittsburgh
July 1, 1941 - The first commercial television station began broadcasting.
April 3, 1973 - Martin Cooper of Motorola makes the first cell phone call in history.
As you can see, both states and businesses have understood that radio is information, money, power.
But scientists and engineers did not stop, they were excited by radio waves capable of transmitting, heating, having different lengths and speeds. Radio stood at the service of science and still stands on it. It seems that it will stand for more than one decade. Today we will recall the most unusual and important inventions in which the radio was not a tool or a means, but a full-fledged co-author.
Development of electronics. Radio simply built electronics and microelectronics: devices, televisions, receivers, transmitters required a huge number of circuits, boards, complex and simple components. A whole giant industry has worked and is working for the radio industry.
Radio astronomy. Radio telescopes have made it possible to study objects in the Universe (although the signal is a long time by earthly standards - from several seconds to several hours) by studying their electromagnetic radiation and the range of radio waves. Radio astronomy gave a huge impetus to all astronomy, made it possible to obtain data from lunar rovers and rovers, to see in space what the most powerful optics are not capable of.
This is what radio telescopes look like (Paul Wild Observatory, Australia)
Navigation and radar aids - also a merit of radio. Thanks to them, you need to try to get lost in the most remote areas of the planet. It is the radio that helps to create and use the most accurate maps, the most sensitive trackers and ensures the interaction of machines with each other (M2M). Here it is worth mentioning radars, without which the automotive industry and transport would have developed several times slower. Radar has played a huge role in military affairs, intelligence, the development of weapons and military vehicles and ships, in science, underwater research and much more.
How a satellite navigation system works.
Cellular communication and the Internet. Remember the terms Wi-Fi, Bluetooth, CDMA, DECT, GSM, HSDPA, 3G, WiMAX, LTE, 5G? All these technologies and standards are essentially nothing more than an oscillatory circuit, discovered in 1848. That is, the same radio waves, but only with different speeds, "range", frequency. Accordingly, it is radio that we owe for those things that occupy our minds today - in particular, the Internet of things (things communicate over a radio channel), smart home, various integrated information collection technologies, etc.
Surely each of you saw these towers close (white boxes - base stations of operators, BS-ki). The intersections of BS coverage areas define "cells" - cells.
Satellite connection is a standalone achievement. Radio waves have made it possible to obtain the advantages of wireless communication where it is impossible to organize a cell - in remote areas, in the mountains, on ships, etc. This is an invention that has saved lives more than once.
Satellite phone
Eiffel Tower. Built for an international exhibition in 1889, it was supposed to stand for only 20 years and was doomed to be taken apart. But it was this tall building in Paris that became the tower of radio broadcasting, and then of television broadcasting and communications - accordingly, they changed their minds about demolishing such a useful contraption, and it gradually became the main symbol of France. By the way, they do not leave the workplace - base stations, transmitters, dishes, etc. are still fixed on the tower.
How do you like this angle of the symbol of France?
radio wave surgery (not to be confused with radiosurgery!). This is an advanced surgical method that combines tissue sectioning and coagulation (βsealingβ vessels so that there is no bleeding) without mechanical action with a scalpel. The principle of operation is as follows: a thin surgical electrode gives high-frequency radio waves, which are generated by alternating current with a frequency of at least 3,8 MHz. Radio waves heat the tissues, evaporate cellular moisture and the tissues disperse bloodlessly at the incision site. This is a fairly low-traumatic and painless method (most often used under local anesthesia), which is also common in aesthetic surgery.
Device for radio wave surgery BM-780 II
Of course, you can recall certain types of locations, microwaves familiar to us, therapeutic experiments, of course, numerous and diverse radio stations, the whole world of radio amateurs and many other examples - we have given the most extensive and interesting ones.
In general, guys, signalmen and those involved, happy holiday! Traditionally: for communication without marriage, purity of frequencies and not a single gap.
73!
The postcard was prepared by the team β we not only create CRM systems, but also try to make a feasible contribution to the life of TV and radio holdings, so we have developed a cool industry solution for them . By the way, tested for 19 TRX π
Source: habr.com