Invention of the radio

This article deals with the invention of the radio in technical terms and its beginnings as a medium. On the development of radio broadcasting structures : ↑ see History of radio broadcasting .

History of the invention of the radio (timetable)

1820		- HC Ørsted - First observation of electromagnetism , further research by A.-M. Ampere , F. Arago, and M. Faraday
1861		- JP Reis - First wired intercom / hearing aid, basis for later telephones and headphones
1873		- JC Maxwell - Wave Theory
1881		- C. Ader - Invention of wired radio, the theater
1886		- T. Calzecchi-Onesti - invents the first coherer .
1888		- H. Hertz - Evidence of Electromagnetic Waves Predicted by Maxwell. A 10 meter wide transmission is possible.
1892		- DE Hughes - First wireless electromagnetic transmission of Morse code
1893		- N. Tesla - Demonstrates its wireless transmission.
1895		- AS Popow - Successful transmission 190 m.
1901		- G. Marconi - Successful transmission of a Morse code across the Atlantic.
1906		- GW Pickard - patent for the first detector component on semiconductor basis . (Replacement of the coherer) - V. Poulsen - Introduces arc transmitter , transmits language and music as the first. - R. Fessenden - First transmission of speech and music with a program character .
1909		- CD Herrold - First news broadcaster
1910		- French Post and Telegraph - First time signal transmitter on the Eiffel Tower
1916		- F. Conrad - First radio program
1919		- H. Schotanus à Steringa Idzerda - First commercial radio station
1926		- NBC - North America's first national (nationwide) radio station
1929		- Radio Moscow - First international radio station

The story of the invention of the radio ( Latin radius 'ray') is a series of events during the 19th and first half of the 20th centuries. It is part of the history of technology and also of the media history of that time.

reception

The invention of the radio is technically based on:

• scientific research , especially on electricity and magnetism as well as other sciences,
• communications technology inventions, especially telephones and radiotelegraphy ,

and in media terms on media etc. a .:

• like today's historical telegraphy for the transmission of characters and telephony for voice transmission.

Technical aspects

The rise of radio ( Swiss German Rundspruch , English radio broadcast ) in the 1920s and 1930s again influenced the development of better transmission , reception and recording technology for radio.

The scientific knowledge about the properties of technically usable electromagnetic waves, the radio waves , enabled the emergence of the scientific discipline that

• Radio astronomy and the invention of the
• Radar (abbreviation of Ra dio D etection a nd R was concerned) for which Dektion of objects, according to the reflection of radio waves.

The development of radio subsequently influenced the development of television , including various inventions of television technology , in particular for wireless transmission. The audio signal and the new second radio signal with the image information, the television signal , which is now required for this , were initially broadcast on the first television, so-called mechanical television , via medium wave with existing radio technology .

In addition, the emergence of radio technology for several radio services , especially voice radio such as marine radio , which previously only communicated via Morse code , aeronautical radio and radio navigation and location was influenced.

Aspects as a medium

The invention of the radio enabled the emergence of the radio in the sense of radio as a one-to-all medium or auditory tertiary medium and the development of the first electronic mass medium .

A medium that for the first time

• broad impact (high media coverage ),
• regardless of social status,
• could be used without special knowledge and skills as well
• The receiving devices required for this were to be manufactured inexpensively industrially or in self-construction.

This simple possibility of participating in this medium also opened up new perspectives for the population to participate in social life and political activity. These properties of the medium of radio and radio were significant, including their evaluation among contemporary authors of the 1920s a. a. in Germany such as B. H. Bredow and others controversial and commented differently. Several radio theories dealt with the medium of radio or radio .

Development of technology

overview

The technical tasks for operating a radio are:

• the generation, provision and, if necessary, the storage and retrieval from sound storage media such as a record , the sound signals to be transmitted ,
• the modulation of the audio signal on a carrier wave so that it can be broadcast,
• the transport, the transmission of this signal to the receiver in the form of the propagation of radio waves and ultimately
• the reception and processing or reconversion of the signal in receiving devices and output from sound and thus into tones that can be perceived by humans.

Scientific research into physics , chemistry and mathematics from the 17th to 19th centuries was necessary as the basis for success . Findings about materials as conductors , semiconductors and non-conductors , about acoustics , about electromagnetism , electrical conductivity , charge and discharge as well as the behavior of magnetic fields as well as knowledge about the functioning of apparatus, components and elements, in particular antennas , coils , capacitors , resistors , Isolators and batteries and measuring devices as well as the calculation of individual processes and parameters to determine the parts to be used.

Generation and provision of a signal

The direct generation and provision of the audio signal is followed by conversion in order to prepare it into a signal for transmission. To use it serves as a source

• playback - to use a sound recording made at an earlier point in time (e.g. a radio play ) or
• the use of a source producing sound at the moment (e.g. a pianist playing).

Sound recording inventions

Edison, Berliner and Poulsen

In 1877, the American inventor Thomas Alva Edison presented a tin foil phonograph , his first usable and still purely mechanical storage method, the sound recording . The phonograph was replaced by the gramophone , which the German-American Emil Berliner , a graduate of the Cooper Institute, invented a decade later. With the telegraphone , the forerunner of tape recorders , the Danish physicist Valdemar Poulsen developed another method of recording. He obtained the patent for it in 1898.

Apparatus of this type and their further developments at that time were of great importance for radio, because z. B. Music, speeches, radio plays or programs for language lessons could be recorded and broadcast completely independently of the recording location and time and as often as desired. This offered an alternative to the more complex direct transmission of sound works that had to be transmitted immediately from the studio or elsewhere.

Inventions for sound conversion

Scientific basis

→ Main article : microphone

The sound conversion is to convert the process, the sound waves of the presented or recorded sounds such as speech, music, noise in this frequency range present in the same electrical vibration. Findings about electromagnetism and acoustics were important for the development . Mention should be made of Joseph Henry , Hendrik Antoon Lorentz , Charles Augustin de Coulomb and Hermann von Helmholtz .

Rice, Bell, Hughes, Hunnings, and White

In 1861, the physicist Johann Philipp Reis was the first to invent a useful device capable of converting sound into a weak electric current and vice versa. The Reis'sche telephone worked like this on the model of the human ear (see picture below):

• When speaking in a sound funnel (similar to the ear canal ) closed by an animal skin as a membrane (similar to the eardrum ), the sound pressure created increased movements of the air molecules, which set the membrane vibrating and thus could push a platinum plate away from a resetting spring .
• The movements triggered a current that was diverted via a wire.
• The conversion back (listening) was done using a knitting needle made of iron, moving in the same rhythm. It was located in a coil made of copper wire wound around it, through which the current generated by the speech unit (the contact microphone) flowed and caused the needle to move. Here a wooden box in which this device was installed served to amplify (like the entrance funnel) the sound waves to be heard. Reis called his invention the telephone . However, the value of this device was not recognized in Reis' home country Germany at that time, so that his invention ultimately served as the basis for further creations by others. The invention achieved international fame because Reis also sold numerous demonstration models that he had Johann Valentin Albert made in the USA.

A further development of the speech unit of the Reis'schen Telephone , the microphone, was achieved in 1876 by the inventor Alexander Graham Bell himself, and a year later by his employee Emil Berliner. Berliner added a piece of graphite , a material that was used in electric motors at that time . The actual inventor of the carbon microphone is considered to be the Welsh-American scientist David Edward Hughes , a US-American-British scientist who, like Bell, bought a sample device from Reis and further improved the principle of the contact microphone.

Thanks to Henry Hunnings , the microphone as a sound transducer experienced a further increase in quality in terms of speech intelligibility with the use of even finer graphite bodies, the carbon grains as sticks and bits. Ultimately, in 1890 , Anthony C. White (registered as US Patent 485311 on November 1, 1892) designed the first principle of the studio microphone. The material graphite was later replaced by electrographite with better properties.

The graphite-based type of microphone was used all over the world for radio and later television for another three decades, and in the mouthpieces of telephone sets even until the 1970s.

Development of transmission technology

The next task is to transport the signals generated by sound conversion or stored by sound recording to the receiver. In the middle of the 19th century, a special time began for communications technology as a whole, especially radio, with many inventions and experiments aimed at wireless transmission.

Scientific basis

Contributing Scientists

F. Arago 1786-1853 M. Faraday 1791-1867 AT THE. Ampere 1775-1836 JC Maxwell 1831-1879 H. Hertz 1857-1894

Ørsted, Ampère and Arago

Findings from the 18th and 19th centuries, especially from two areas of science, physics and mathematics, were important for wireless transmission. The first observations of magnetic abnormalities are made by Hans Christian Ørsted , André-Marie Ampère and François Arago .

Faraday, Maxwell, and Ruhmkorff

The British polymath Michael Faraday described the observations of Ørsted, Ampère and Arago in his book "Historical Sketch of Electro-Magnetism" and summarized the first conclusive theories of these scientists. With this scientific work, Faraday laid the scientific basis for many technical inventions together with his successful and very extensive experiments on electricity and magnetism. In addition, Michael Faraday and Heinrich Daniel Rühmkorff (or other spelling Ruhmkorff ) developed various models of spark inductors , the basis for later oscillators .

The Scottish physicist James Clerk Maxwell followed up Faraday's work by systematizing them from the 1860s and visualizing them in differential equations , the four Maxwell's equations named after him . In 1871 Maxwell's wave theory emerged , with which he predicted that an electrical discharge would generate vibrations just like a stone thrown into water . A time oscillating electric field generates a time-oscillating magnetic field . If the latter in turn creates an electric field, the electromagnetic field that spreads through it is an electromagnetic wave . Maxwell's theory was an important contribution to the technical fundamentals of the transmission of information .

Scientific experiments

Experimental set- ups from the Hertzian oscillator and Reis' telephone

Heinrich Hertz

The physicist and mathematician, Professor Heinrich Hertz checked Maxwell's scientific statements through experiments from 1886 to 1888. For this he developed an oscillator, an apparatus for generating vibrations, with which Hertz was able to prove the correctness of Maxwell's wave theory and the existence of electromagnetic waves. In 1888 Hertz achieved the first transmission with his oscillator and a spark inductor over a distance of 10 meters to a receiving dipole , which acted as a resonator (see picture above). For his oscillator experiments, he alternately used several existing devices, for example inductors (Faraday and Ruhmkorff), Leiden bottles and coils (Reiss and Kniehauer)

With his work, including validating the work of his scientific colleagues from Ørsted to Maxwell, Heinrich Hertz pioneered wireless transmissions for wireless telegraphy and radio. The unit of measurement that represents frequency, for example on the scale of radios and radios, bears his name - Hertz ( Hz ).

Pioneering work

The first possibility of wireless transmission known in the 19th century was induction in the form of near-field coupling . This means that only short distances can be bridged, depending on the current strength and equipment. This principle is used, among other things, in transformers , but does not allow an acceptable radio range for the transmission of information signals.

The pioneers of wireless transmission for communications technology were not just scientists, but increasingly engineers and interested laypeople as well. This phase was characterized by partial successes, empirical procedures by means of experimental extensions and errors, parallel developments and failed attempts. It was also noticeable that in the end no one managed to be successful in either telegraph or radio technology. Guglielmo Marconi , who contributed to the practical implementation of radio telegraphy, said:

My chief trouble was that the idea was so elementary, so simple in logic that it seemed difficult to believe no one else had thought of putting it in practice

From Hughes to Tesla

David Edward Hughes developed the Reiss telephone further. He added graphite rods to the radio unit. In 1878 he began experiments with his own induction-based speaking device, which he equipped with this carbon microphone. As a result, he presented the " Royal Society " in February 1880 with a device that reproduced previously spoken words. This was the first time that Hughes transmitted speech signals, which, however, could not yet be identified as speech, but rather as noise.

Over the next few years, other inventors with similar devices followed, such as the American Nathan Stubblefield and the Brazilian Roberto Landell de Moura . However, they have not yet made the breakthrough either.

Four months after the Hughes presentation, on June 3, 1880, Alexander Graham Bell and Charles Sumner Tainter succeeded in demonstrating a technique that is considerably superior to induction in terms of quality and range. This much more effective option of wireless transmission worked using bundled light beams . Bell and Tainter constructed a 'light telephone' and invented the photophone for this purpose . Although this was the world's first successful wireless transmission of intelligible language at all, this technology did not catch on and thus gained no future importance for the development of the telephone, telegraphy or radio. However, the principle is used in a different form in current communications technology, for example as an optocoupler and in optical directional radio .

Drawing of the experimental setup by Branly with his coherer

In 1886, the Italian physicist Temistocle Calzecchi-Onesti was the first to invent what was then an important component for receiving radio waves - the coherer , which was also known as a fritter. The component consisted of electrodes and a glass tube filled with metal filings. However, the early invention of the Italian was hardly noticed and, like the Reiss telephone, had no direct influence on the development.

In 1890, independently of Calzecchi-Onesti, the French physicist Édouard Branly developed a coherer, as did DE Hughes, who used the component for the receiver he designed. In his reply, which was published from 1861 to 1952 by the renowned British technology magazine "The Electrician" , published in 1899, DE Hughes describes the experiments he carried out between 1879 and 1896. As a result, he no longer worked with induction transmission during the tests, but with one along the lines of the oscillator by Heinrich Hertz, the Hertz oscillator , further developed so-called spark-gap transmitter ( english spark-gap transmitter ). The transmitter and receiver of the Morse code to be transmitted were located in separate rooms within Hughes' apartment on Great Portland Street in London . DE Hughes' experimental set-up covered a distance of 15 m in 1892, which he was able to increase to 500 m outdoors. Information about the quality of the transmitted signals is not described in the literature.

Nikola Tesla , a Serbian-born inventor who did his essential work in the United States, began studying the subject of wireless power transmission in 1891. In 1893 he presented devices that could use high-frequency energy transmission to light up freely movable Geissler tubes in a room , but he was also unable to send voice signals. His contribution to the development of the radio is to enable more reliable, more stable frequencies through his attempts.

Oliver Lodge

The British physicist Oliver Lodge presented the " Royal Society " in 1894 with a transmitter and receiver. For his receiver, Lodge, like DE Hughes before, replaced the dipole used by Hertz on the receiver side (the resonator in the experiment set up by Hertz in 1888) with a coherer. He used Édouard Branly's coherer from 1890 and developed it further. Telegraph component manufacturer Alexander Muirhead was involved in O. Lodge's work.

The transmission with this technology allowed the transmission over the distance from building to building like between the "Royal Society" and a neighboring lecture hall. Lodge's combination of transmitter and receiver also represented the basic construction or a sample product, with which everyone could experiment in the future. The developments by Guglielmo Marconi, Adolf Slaby , Alexander Stepanowitsch Popow , Ferdinand Braun and others were variations based on O. Lodge's apparatus.

From Bose to Baviera

In the same year 1894, the Indian physicist, Jagadish Chandra Bose, demonstrated the ringing of a bell or bell, switched on by radio remote control by a radio transmission over a distance of about 1.6 kilometers. The Russian physicist Alexander Stepanowitsch Popow bridged 190 m with his apparatus in the State University of Saint Petersburg on May 7, 1895 and published his device description in a Russian specialist journal in December 1895 without applying for a patent. On March 24, 1896, his test arrangement sent the 13 letters HEINRICH HERTZ to a receiving station 250 meters away. In France he worked with the French inventor Eugène Ducretet , who also attempted transmission, as well as with Édouard Branly, whose coherer he used for his receiver. Alexander Stepanowitsch Popov also conducted experiments on ships of the Russian fleet and in 1900 came to a distance of 112 kilometers. For his pioneering achievements, Popow received honors at the 1900 International Electricity Congress in Paris.

In 1895 Guglielmo Marconi presented his first wireless transmission device, with a remote-controlled bell 1 kilometer further away than Bose's. In the summer of 1895, during further experiments in the Swiss Alps in the Valais town of Salvan , he discovered that, contrary to previous doctrines, radio waves do not only propagate in a straight line. This pop spark transmitter worked according to the following principle:

• The first capacitor was charged to a high voltage until the arc ignited at the spark gap.
• If the spark jumped over, this caused a loud bang, a parallel connection was created with the capacitor on the other side and the high-frequency and damped oscillating transmission current was created, which was emitted via the antenna.
• To repeat the process to send again, the capacitor had to be discharged. Only a series of damped vibration packages could be emitted.
• The process of charging-sending-discharging was not very effective, because an acceptable level of efficiency could only be achieved with high voltages of a few kilovolts.

Marconi with a transmitter and receiver, around 1901

From the statements of Marconi's daughter Degna, it is not clear whose coherer her father used specifically for his reception attempts , quote: “ a tube of glass with pulverized metal based on much that was already published by Hughes, Calzecchi-Omesti, Branly and Lodge ”. That confirms that Marconi knew them all. In his memorandum (lecture) Wireless telegraphic communication on the awarding of the Nobel Prize to him, he wrote in 1909 that he initially used E. Branly's coherer, but it turned out to be of no use to him. Which one he used instead is not published. In the Nobel Lecture he describes: His experimental set-up for the transmitter is based on a further development of the Hertzian oscillator by the Italian physicist Augusto Righi and that the coherer has been improved due to the fact that the material changed from nickel / silver to two silver contacts. In 1897, G. Marconi achieved wireless transmission over a distance of five kilometers with his selected technology. 1899 he succeeded to bridge the English Channel and in 1901 the entire Atlantic, where he the Morse code of a letter, the S transferred.

The officer Julio Cervera Baviera (* 1854, † around 1929) from Madrid undertook his own experiments after completing his assistant at Marconi and in 1899 applied for patents for wireless transmission technology in Spain. In 1902 he covered a considerable distance in a transfer between Alicante and Ibiza from

Attempts to send sound

Due to their functional principle, the pop-spark transmitters that had existed up to that point could only transmit signals in a subdued form . The further development from a pop to an extinguishing spark transmitter did not change anything. This transmission technology could not yet become the basis for successful sound transmission attempts.

Duddell, Poulsen, Pedersen and Nussbaumer

The British physicist William Du Bois Duddell undertook the first promising experiments with arcing . In December 1900 he presented his " Singing Arc Lamp ". The physicist and engineer Valdemar Poulsen from Denmark, at that time already known for his invented telegraph , developed an arc transmitter from Duddels Lamp in 1902 . In contrast to the pop spark transmitter, two different electrodes were used. An air- or water-cooled rigid, positively charged and made of copper electrode, and a negatively charged electrode made of carbon, which rotates around the first. If the DC voltage is sufficiently high, which is fed to the electrodes via choke coils , an arc is created there. As with the spark gap from transmitters of damped waves, an induction coil is connected parallel to the poles of the arc , which then dissipates the transmitted energy via the antenna.

V. Poulsen and his colleague Peder Oluf Pedersen , also a physicist, worked together until 1904 to improve the coherer as a receiving component for the so-called " Tikker " (meaning: knocker), a kind of interrupter, also known as a grinder according to the literature, whereby the spoken words sent by means of an arc transmitter Words were perceived as a buzzing sound. Thus, it has been proven that this method, which has been refined in terms of transmission quality, now received wirelessly transmitted audio signals. The arc transmitter enabled the transmission of undamped signals . This uniform transmission, which was now possible for the first time, not only enabled sound transmission, but also revolutionized the rest of wireless communications technology, since telegraphy or Morse code signals could be transmitted much more clearly and without interference. Another European, Otto Nussbaumer , also experimented with arc technology and built his own transmitter and receiver with which he could transmit speech and music.

The US “ National Bureau of Standards ” stated the sudden increase in effectiveness achieved by V. Poulsen's technology as follows: “ The arc is the most widely used transmitting apparatus for high-power, long-distance work. It is estimated that the arc is now responsible for 80 per cent of all the energy actually radiated into space for radio purposes during a given time, leaving amateur stations out of consideration . "In 1907, the popular mechanics magazine in the USA headlined: “ Poulson wireless progressing ” “ that Valdemar Poulsen after his longest achieved transmission distance of sounds over 760 miles (corresponds roughly to the distance between Copenhagen and the Faroe Islands in the Atlantic ) - shortly a pedant to his transmitter Lungby in Denmark in the USA is erected to enable the transmission of sound signals across the entire Atlantic ”( Popular Mechanics : June 1907).

The industrial production of the transmitters by V. Poulsen under his license was mainly carried out by C. Lorenz and Telefunken , especially for Europe . They ensured that the technology was widely used, especially in Germany, Poland and Austria.

Fessenden, Steinmetz and Alexanderson

Reginald Fessenden and Charles P. Steinmetz as well as Ernst Fredrik Werner Alexanderson undertook a different way of generating undamped waves and constructed machine transmitters, which were originally called alternators and which produced radio waves by means of a motor that drove a generator. The first company to manufacture these alternators for the machine transmitters was General Electric from the USA. The last still functioning long-wave transmitter Grimeton (callsign SAQ) of this kind is a museum transmitter in Grimeton in southwest Sweden .

With the further development of electron tubes , it became possible to manufacture powerful transmitter tubes . Both transmission technologies of the early years, arc and machine transmitters, were gradually replaced by stations with tube technology, the tube transmitters . Only the transmitters with tube technology enabled the transmission of speech in a high quality.

The reception technology

Scientific basis

Ferdinand Braun

The receiver technology in the experiments on wireless telegraphy by Branly, Popow, Marconi and a few others already worked according to the same principle of the simplest receiver, the straight-ahead receiver in the variant of a single circle . But there was no semiconductor detector for rectification in the oscillating circuit - as in the first radio devices, instead a coherer or fritter was still present as an inductor receiver component. And this had too little sensitivity to be able to receive and reproduce speech or even music.

The German physicist Ferdinand Braun observed an anomaly in electrical conductivity in non-metallic materials such as lead sulfide, contrary to Ohm's law . With his publication in 1874, he discovered and described the rectifier effect of semiconductors for the first time, “About current conduction through sulfur metals” . Presumably because Braun later collaborated with Marconi on experiments on wireless telegraphy and both experimented on transmitters that were not intended for the transmission of audio signals, Ferdinand Braun's remarkable results of his early semiconductor research did not flow into these experiments. It is not known whether Braun did not recognize the chance if semiconductor crystals had already been inserted into their receivers or whether something else prevented him from using reliable and more sensitive crystals instead of the coherer. Neither Braun nor Marconi had any direct influence on the development of radio technology on the receiver side.

Semiconductor detectors

Greenleaf Whittier Pickard

The experiments of the American engineer Greenleaf Whittier Pickard from 1902 made it possible to replace the coherer. In addition to galena, Pickard also experimented with pyrite , finding a total of over 250 materials with semiconductor properties. In 1906 he applied for his first patent, US patent 836531 with the name Means for receiving intelligence communicated by means of his silicon detector , a glass tube in which a small amount of silicon and from the poles of the material an adjustable and an outgoing rigid one Contact found. About seven more followed, in which he used other materials or their combinations. In 1907 Pickard succeeded in producing an even more effective semiconductor detector, which consisted of a combination of zincite and calchopyrite , so-called copper-iron sulfide or copper stone . For this he also developed a new holder in a glass tube with a much smaller diameter than before. The detector was named "Perikon" , also Pericon , (Perfect Pickard contact), and Pickard founded his own company for production, the "Wireless Specialty Apparatus Company" in Boston .

With his extensive experiments on the component of the detector, GW Pickard created the basis for the first type of capable and stable radio receiver: the detector apparatus , which was also known as the crystal receiver .

At the same time as Pickard, Jagadish Chandra Bose also conducted research in this area and in 1904 patented a galena detector. Henry Harrison Chase Dunwoody developed another detector component in 1907 . It should be mentioned that Ferdinand Braun later also developed a detector and registered the patent for this component, but could only do this in Germany (patent DE 178871).

It should be noted that at the beginning of the 20th century the term detector originally only referred to the component itself (e.g. cat's whisker detector ). In the following, those receivers that were equipped with a detector module and thus operated according to the detector principle were referred to as detectors, detector receivers or apparatus as a whole.

Straight-ahead receiver

The detector receiver

The simplest form of a circuit based on the detector principle. The largest of the 5 elements in the illustration is the resonant circuit coil with a slide for transmitter setting

High-impedance headphones for radio reception, a capsule is open and shows the magnetic coil.

The detector receiver belongs to the group of straight-ahead receivers . DE Hughes developed the telephone, invented by JP Reis, into a component of the carbon microphone - due to its construction, depending on where it was connected, it allowed either speaking or listening. When connected to a detector receiver, hearing was possible. The connection sockets for the listener on the first radio receivers were accordingly also labeled with Telephon . Names such as headphones or earphones followed only later . The earphones were further developed with the use of magnetic coils and soon replaced the ones mentioned at the beginning based on a carbon microphone.

With the latter and the semiconductor detector described above, all the components that a receiving device needed existed. These five parts only had to be connected in a circle when viewed from the current flow (see picture on the left):

	1.	an antenna,
	2.	a receiving coil (tuning coil),
	3.	a rectifier made of silicon, galena, pyrite or other materials (detector),
	4th	a ground connection to the mass (ground) and ultimately
	5.	one or more (headphones) headphones, depending on how many people wanted to hear with the device.

Crystal detector, mounted on a vertical slide coil, the slide of which is used to tune the transmitter, 1925 from Jahnke Mechanische Werkstatt, Berlin N31

Drawing of an Audion tube that was patented in 1909, with the spherical shape and the then contemporary socket (E12), reminiscent of the technical relationship to the incandescent lamp.

Later, as a further development of the receiver, one or two capacitors and a resistor were added. A particular advantage of this device was that it did not need any electricity and, thanks to its operating principle, gained the energy it needed from the energy emitted by the radio transmitter. However, initially only so-called local or local reception was possible. Remote reception was and is a worthwhile goal for radio amateurs and radio hobbyists.

Up to the present day DX competitions are held with crystal receivers, in which they measure their skills in the manufacture and selection of their devices and components. There are also still industrially manufactured small kits around the world with which this simple receiver can be built. The most famous construction kit in Germany was for almost 50 years the "radio man" of the Franckhschen Verlagbuchhandlung (later Kosmos) in Stuttgart.

The Audion receiver

Lee De Forest from the American Midwest developed a more powerful straight-ahead receiver . In 1907 he patented the Audion (made up of Latin audio = to hear + n), as he called his invention. The most important new component compared to the detector was a triode . Lee De Forest developed it after John Ambrose Fleming invented the first electron tube , a tube diode . Robert von Lieben created a similar tube in Europe parallel to Lee De Forest, which could also be used for amplification, the so-called love tube.

The first Audion, which achieved a high distribution in German-speaking, was the 1926 mass-produced local receiver OE 333 the company Loewe Radio GmbH . Together with Manfred von Ardenne, Siegmund Loewe developed 2 electron tubes for this single-circuit audion , which, similar to today's integrated circuits, both represent two combined components, in which, in addition to the components for the actual tube functions of triodes , those for a receiver or an amplifier circuit accordingly required resistors and capacitors were integrated. In order to be able to receive radio transmitters outside of cities with broadcasting stations, the Loewe company produced another model, a remote receiver.

Another significant improvement in the straight-ahead receivers was the multi-circuit . This meant that, in addition to the first resonant circuit consisting of a receiving coil and a capacitor, additional input circuits for amplifying, selecting or filtering were added in front of or to amplify the audible signal. In the case of only one additional circle this was a two-circle receiver, with others - a multi-circle receiver or, depending on the total number of circles, three, four, five-circle etc.

This method of additional circles could be used for the detector as well as for the audion mainly to improve the selectivity, the volume and / or the reception quality. Improving electron tubes and later also transistors made a higher number of circuits possible. However, more than three circles were unusual for the detector.

Although the heterodyne receivers began to replace the audion in the late 1930s, radios with audio circuits continued to be manufactured industrially until the 1970s. With radio and radio amateurs , Audion receiver circuits as self-assembly ( English homebrew ) or in the form of kits are popular up to the present day. In addition to a high degree of selectivity , a feedback audio in particular also enables the reception of SSB transmitters , for which a superimposed receiver requires an additional receiving device.

Drawing of the Radiola superhet AR-812, 1924 from RCA Victor Co. Inc., New York

Rotary film capacitor for transmitter tuning in the form of a squeezer

Transition to the superhet receiver

The development of yet another group of recipients, the superhet or superimposition recipients, began as early as around 1918 . From the initially long made-up word superheterodyne (Latin super = over; ancient Greek hetero = different and dynamis = force), the word super or radio super has remained as a designation for this group.

Because of the much simpler construction of the straight-ahead receiver, the Super could not prevail for a long time, and so the straight-ahead receiver Detector and Audion were initially the favorites with the audience in the first two decades of the radio age. Shortly after the Second World War , audion and the detector became increasingly popular again in Europe, presumably due to the lack of raw materials and lack of money. To be read on the basis of a boom in publications of many self-assembly instructions of these two types in magazines and other publications for technology, in German-speaking countries for example Radio RIM from Munich. Exact sales figures cannot prove this, however, as information about the black market , a distribution channel during this time and the like. a. of technology and self-made are not available.

However, the emerging VHF radio gradually put an end to the further industrial development of straight-ahead receivers, as this wave range, with the exception of a super-regenerative receiver , the so-called pendulum audio or pendulum receiver, could only be received by a superhet (erodyne) device.

Loudspeaker operation

As with gramophones, the first loudspeakers without amplifiers had the shape of a funnel or horn.

Werner von Siemens designed a component with a horseshoe-shaped magnet - for reproducing sounds. He even filed a patent application for it in Germany in 1877, but this early invention was not yet feasible. A “new” invention of the first loudspeaker based on Siemens' developments took place. In order to use such a magnetic loudspeaker on a radio receiver such as a detector or audion, in contrast to a simple receiver or funnel, a stage with an amplifier for the audio signal usually had to be switched in between. With the use of the amplifier stage, the sound-amplifying funnels were no longer required.

The design

The range of shapes of the early devices ranged from the simplest board circuit through the box, box and desk shape to the cathedral, a front view and housing type inspired by the church windows.

The appearance of the radios became more and more sophisticated even with the first devices. Especially from the point in time when playback via loudspeakers became technically possible or other new components were added as elements to be designed. Ornate decorations, elaborate wood inlays , veneer gluing and fabric panels often turned the radio into a real showpiece. There were no limits to size either. From the table top to the music cabinet, everything was represented. The introduction of the variable capacitor was a further technical advance, as it enabled a further change and simplification of the housing construction and the arrangement of the control elements of a receiver due to the considerably reduced space requirement for the element for transmitter search. The radio developed in several steps from being a laboratory apparatus that was initially purely adapted to technical requirements to becoming an elegant piece of furniture.

• 

  Two forms of the 1930s: Superhet Superette R9 from Radio Corporation of America as a floor-standing device and the R7 (right) as a tabletop device.

• 

  Superette R7

• 

  Girls at a representative radio in a box shape .

• 

  Crystal detector on a desk molded case from 1925 from Japan, imprinted with the identifier JOAK, the first Tokyo station.

• 

  Shapely Gloria SW3. Manufactured in 1929/30 by Lumophon, Bruckner & Stark Nuremberg

• 

  Drawing of a cathedral shape , strictly speaking a window of a cathedral.

The beginning of radio broadcasting

→ Main article : History of radio broadcasting

Development of the forerunner

Teatrophone

The wired model of radio was the theatrophone invented by Clément Ader . As early as 1890, the Société générale des téléphones broadcast opera works from Paris by telephone and expanded the program to include broadcasts of plays, news, works of the new genre of radio plays , language courses and stock market reports. This technology was used just as successfully in Great Britain ( Electrophone ) and Hungary ( Telephone Hírmondó ) as well as in Sweden, Belgium, Switzerland and Portugal. In contrast, the wired radio from the telephone line found less response in Germany, Austria and overseas. However, due to the development of radio, this medium hardly had a chance of survival in this form after 1920, although it could even broadcast stereophonic .

Wire radio

A procedure similar to the theater, the wire radio was used during and after the Second World War . In contrast to the teatrophone, wire radio usually did not generate its own program, but was simply a further means of transmission in addition to the wireless broadcast by an existing radio station. In the Second World War, wire radio was used for air raid warnings . After the end of the war, for example, the forerunner of RIAS was set up in Berlin , the wire radio in the American sector DIAS, whose radio program was transmitted over the telephone network. During this time, in addition to Germany and Austria, three public service programs could be received via wire radio, but their operation was discontinued after 20 years.

Telephone slogan

In order to offer radio broadcasts in areas that were still poorly received or completely free of transmitters, radio programs from existing radio transmitters were also transmitted via telephone wire in other countries, especially after the end of the war in 1945. Frequently, regular, mostly selected radio programs were broadcast at the same time as the broadcast of a respective radio station.

The USSR had the largest network for this purpose. In Switzerland, where the telephone broadcast (TRS) was already available from 1931 in parallel to the wireless broadcast , mainly for mountain valleys that were difficult to reach within a transmission area, an extension to the high-frequency telephone broadcast (HFTR) took place from 1940. In 1956 there was even an increased expansion. In Italy, too, there existed from 1959 parallel to the terrestrial broadcast of the RAI radio via wire radio, the filodiffusione .

However, with the beginning of ISDN transmissions and the increasing spread of radio broadcasting on VHF transmitters, these services via telephone network lost their importance. They were therefore greatly reduced in Italy and largely switched off in Switzerland in 1998. An HFTR system only works in the Swiss Federal Palace for the transmission of debates from the councils . In Italy's major cities, six RAI channels that can be heard by wire remain from the former nationwide coverage.

Wireless broadcasts

Time transmitter

The transmitting antenna that was formerly attached to the Eiffel Tower (around 1914). Their arm-thick main ropes are black, the cross ropes are shown in a different color. Since then, there has been an underground broadcasting studio under the mast (yellow) that was still in use today.

The transmitter installed on the Eiffel Tower in Paris began the first regular broadcast of a time signal within a radius of thousands of kilometers in 1910 .

Around 1914, as shown in the edited photograph on the right, a new transmitting antenna consisting of six arm-thick main ropes and two times three cross ropes on each side, which were connected to a small mast in front of the Eiffel Tower, was installed on the tower. It was called TSF antenna (wireless telegraphy French télégraphie sans fil ). Due to the - u. a. The high level of the tower made it possible to receive constant signal levels throughout the North Atlantic and Europe, and for the first time there was stability in reception in terms of frequency, signal strength and quality.

This was of great importance for the development of radio, because it gave radio pioneers and radio amateurs , especially in Europe, the opportunity to construct receivers, improve or tune existing ones and also demonstrate the operation to the public. From 1917, the transmitter built in Nauen, Brandenburg, west of Berlin , as well as the French station throughout Europe, broadcast time signals (↑ see also: Eiffel Tower - Telecommunications Use ).

First attempts with a program character

After Valdemar Poulsen's first successful wireless broadcast experiments, a further developed test broadcast followed at the end of 1906. The world's first radio program to be broadcast was broadcast on Christmas Eve 1906. It consisted of Bible text read aloud, record music from the gramophone and the song " O Holy Night " played live on the violin . For this purpose, a team led by Canadian Reginald Fessenden used a machine transmitter in Brant Rock in the state of Massachusetts on the east coast of the USA.

In the course of 1907, Poulsen tried to achieve greater coverage for his transmissions. From the initial approx. 60 kilometers, he increased the distance to approx. 1300 km. Ultimately, he tried to cross the Atlantic for the first time with a sound broadcast from Lungby near Copenhagen in the east of the USA. From 1909 Valdemar Poulsen broadcast music programs played from the gramophone with his station at Lyngby / Zealand on Bagsværdsee.

Also in 1907 the first program transmission from a ship succeeded. In the British port of Chatham (Kent) , a transmitter from HMS Andromeda broadcast poems and music performed in the breakfast room on board. Due to the secrecy of the Royal Navy , this test broadcast remained unknown for almost a century.

Radio telephony

(For this and the next section ↑ see also below: Tables of international & German-language distribution )

After the successes of V. Poulsen and R. Fessenden, further attempts to transmit sounds as well as speech and music followed between 1907 and 1914, for example by the Royal Navy in the county of Kent in south-east England in 1907 - on the Medway River in front of Chatham.

And u. a. also in Germany, mostly with Poulsen's arc transmission technology . For this at that time new type of transmission of audio signals, the terms radio telephony and radio telephony emerged, in contrast to the existing radio (en) telegraphy in the German-speaking area , roughly comparable with today's terms radio and speech radio .

In 1906, the Berlin physicist Ernst Walter Ruhmer made a " telephone call " via radio telephony over a distance of 3 kilometers. This technology was also used in marine radio . For this purpose radio telephone numbers were assigned. According to the archive of the Deutsche Seewarte , the number of a marine radio station contained the call sign , the transmission frequency, wavelength and at the end the addition A plus the digits 1, 2 or 3. Depending on whether the transmitter in question is still in undamped (A1) or tone-modulated waves (A2) or in radio telephony (A3). (e.g. Norddeich Radio “DAN 122.9kH 2440 m A?”).

The experimental radio station on the Finow Canal near Eberswalde (north-east of Berlin in what is now the state of Brandenburg ), the company C. Lorenz with its multi-tone transmitter, broadcasted tones for the first time in 1910 and Germany's first program-like radio broadcast in 1919, which was regularly carried out in the following years under the name of the concert "To all" was continued.

In 1912 the o. G. Norddeich Radio to test transmissions of speech ( radiotelephone ). Fernando Cardelho de Medeiros carried out the first successful tests in Portugal in 1914. Guglielmo Marconi and the Marconi Company in Chelmsford also began experiments with radio telephony in 1914.

Of the

• o. g. Radio station on the Finow Canal in 1919 and
• 1920 from Funkerberg near Königs-Wusterhausen by Reichspost , in Rheinsberg by Telefunken and a radio station of the League of Nations near Geneva

first broadcasts with music and language were made in German-speaking countries.

Regular program operation

In 1909 , the world's first news broadcaster started operating with 14  watts - with a regular program. The station in San Jose in the US state of California created the physicist Charles "Doc" Herrold and the students in his College of Wireless and Engineering . In 1921, this station, now as a commercial one, was given the KQW code, which CBS later took over.

In 1914 the First World War broke out, which suddenly became an obstacle to the civil development of wireless radio. In various countries, some rigorous measures were taken against radio pioneers and amateurs. They ranged from the revocation of the few already issued transmission and reception licenses to the requisitioning of the first technical devices. This mainly affected the warring nations, but licenses were suspended even in neutral Switzerland.

In 1916 in Pittsburgh the station broadcast with the amateur radio call sign 8XK of Dr. Frank Conrad , former naval officer and employee of the telegraph company Westinghouse Corporation, regularly tests gramophone records and piano pieces played live. Neighboring radio operators were asked for feedback on the radio quality. The music that is always played on Friday evenings quickly developed into a popular leisure event.

In 1917 , the Danish Post & Telegraph took over Valdemar Poulsen's arc transmitter station Lungby and began its first program attempts. This resulted in Lyngby Radio with the callsign OXZ seven years later and then served as a news or marine radio station. In addition, the state company began to broadcast a music program from the OXE station in Lyngby, in 1924 a regular hour a day.

In 1919, the Dutch manufacturer Hanso Schotanus à Steringa Idzerda broadcast the first known regular radio program in Europe from his private apartment in The Hague with the callsign PCGG , four days a week. Until, unfortunately, he had to give up in 1924 because the funding of the program was dependent on voluntary contributions from the listeners, which were not received despite his popular program. It was also difficult that the number of radio stations steadily increased and in the Netherlands a completely new form of organization of radio, the so-called "pillar model" (Publieke Omroep) established by broadcasting associations ( ↑ see also: section of this article below Control ) .

One month (from December 1, 1919) after the PCGG station in The Hague, the XWA ( Experimental Wireless Apparatus ) station was Canada's first station to broadcast its English-language test program in Montreal. The station was owned by Marconi's Wireless Telegraph Company of Canada and began a commercial program in November 1920 under the code CFCF. On June 8, 1919, Lorenz AG broadcast the first broadcast from the Berlin State Opera in Germany .

On August 20, 1920 (now with the callsign KDKA), the first commercial radio station in the USA began regular operations via 8XK. Seven days after the KDKA, the first radio station in the southern hemisphere in South America in Buenos Aires , Radio Argentina (LRO) opened with a theater and concert broadcast.

In 1921 (November 17th) the second radio station in the southern hemisphere and the first in Oceania - the university radio station in Dunedin / New Zealand by Robert Jack . your program in trial operation. In the next year, it was the first volunteer radio in the world to continue operating and it remained as such until 1990. 1921 began in Brazil and France ( "Compagnie or Societé Francaise de Radiophonie" (SFR-P) from the transmitter Émetteur de Sainte Assise and Postes, Télégraphes et Téléphones (PTT) from the Eiffel Tower) first radio transmissions z. B. of events. In the United States, there were 28 more broadcast openings in many large cities and another 70 stations the following year.

In 1922 (July 15), the French PTT broadcast their first radio program from the Eiffel Tower. The first radio station in Uruguay , the third Latin American country with broadcasting, started operations in August of this year. This broadcaster with technology from the General Electric Company broadcast the first known football program and direct broadcast of a sporting event in the world on October 1, 1922. It was the broadcast from Montevideo of the international soccer match in the Copa America : Uruguay against Brazil.

On November 6th, like the PTT, the Eiffel Tower station was followed by France's first private broadcaster “Radiola” of the “Compagnie or Societé Francaise de Radiophonie” (SFR-P) founded by Branly and Ducretet . A few hours later in Great Britain the originally private BBC began broadcasting a program produced in the Savoyen Hill studio, first in London via station 2LO. Birmingham (5 IT) and Manchester (2 ZY) followed a few days later . The BBC was the world's first national broadcaster.

Switzerland began the first commercial use of broadcasting in German-speaking countries in 1922. On the one hand, through regular broadcasts by the " Flugplatzsender Lausanne " and in Münchenbuchsee in the canton of Bern, by a radio telegraph transmitter from "Marconi Radio Station AG" .

In 1923 (May) the company “Radioslava” broadcast its first regular radio program in Czechoslovakia. In September, Spain's first broadcaster “Radio Iberica” also began broadcasting a program.

The radio hour A.G. followed in Germany in October. Berlin (a subsidiary of the " German Hour " ) with a program that is regularly broadcast from the Berlin Vox house . In addition to this Berlin stock corporation, Deutsche Stunden founded further subsidiaries in Germany in order to be able to create additional regional channels. In this context, Munich followed in the same year with the first radio broadcasts. The regional subsidiaries in Germany became members of the Reichs-Rundfunk-Gesellschaft (RRG) in 1925 . From them emerged after 1945 state broadcasters of the later Federal Republic, for example the SDR .

Austria opened in Vienna in 1924, after Radio Hekaphon, for the first time with RAVAG broadcasting operations on the Stubenring ( ↑ see also: table of German-language distribution ) .

Rapid increase in listeners with licenses from the Deutsche Reichspost in the Weimar Republic.

In 1924 (December) the radio of Soviet Russia , later the USSR , started its regular operation with the station "Москва-Лапа" (code ML). The first trial run of ML began as early as 1922. This radio station was the first state or state- owned broadcaster in the world, and from October 29, 1929, it was the first worldwide station to broadcast an international program as Radio Moskwa or Radio Moscow . The first foreign language of the multilingual programs was German. After the end of the Soviet Union, the station, which was renamed Voice of Russia in 1991 , continued operations until March 2014. Since then there is only a limited offer under the name Sputnik and only available on the Internet. The next international stations in other countries followed on December 25, 1929, the program of the German world radio broadcaster (which did not broadcast a self-produced foreign language program until 1932), 1931 Radio Vatican , 1932 BBC Imperial Service and an Arabic one from Italian Radio Bari and 1942 also from Voice of America .

In 1925 , Asia's first radio stations with programs in the local language began their regular operations. That was 3 Japanese stations first the "Tokyo Station" (JOAK), followed by Osaka and Nagoya as well as "Colombo Radio" in Colombo, the capital of today's island nation of Sri Lanka .

In 1929 and in the following two years the first shortwave stations began broadcasting programs in the respective national language, including a. in Germany the aforementioned world radio station and in Great Britain the BBC Empire Service . The aim was to reach their own colonies or overseas parts of the country such as Australia. But also to bring emigrants closer to their original home.

Also in 1929, the first transmitters began to transmit image signals in continuous operation. With a method for so-called mechanical television developed by the Scottish engineer and inventor John Logie Baird , the audio track or the associated audio signal was transmitted on another transmitter, in this case London II (on medium wave 1147 kHz) . Some of the television receivers developed by JL Bairds were called Televisor ( English Televizor ), a term that was adopted early in other languages ​​(e.g. Russian Телевизор and Spanish televisor ). Several of these first generation television sets were also designed so that they could be connected to an existing radio receiver. An example is the Soviet Televisor B-2 .

The radio spread over the entire globe. San Marino was one of the few independent countries that did not have a radio station until around 1975.

Wavelengths and their ranges

Graphical assignment of radio frequencies to wavebands (for an explanation of the abbreviations, see text)

A choice of the wave range (now also called frequency band) such as the wave length or frequency is an important criterion for the range in the communications sense , i.e. the maximum achievable distance at which reception is still possible.

From the pioneering days of wireless transmission attempts to the days of continuous operation of radio transmitters, different frequency bands of the lower frequency radio waves from 3 kilohertz were used for the transmission of the signals, depending on the technical development status. The following areas / bands became possible (in the order in which they were discovered or used for radio):

• Long wave ( English very low frequency or low band , abbreviated English VLF , 100,000–10,000 meters , 3–30 kHz )
• Long wave ( English long wave or low frequency or long wave band , abbreviated LW / LF , 10,000–1000 meters, 30–300 kHz)
• Medium wave ( English medium wave or frequency or medium wave band , abbreviated MW / MF , 1000-100 meters, radio 526.5-1705 kHz)
• Short wave ( English short wave or frequency or short wave band , abbreviated KW / SW or SF , 100-10 meters, 1600-3000 kHz)
• Ultra-short wave ( English very high frequency or very high frequency band , abbreviated VHF / VHF , in the present also marked with FM ^{( frequency modulation )} , 10–1 meters, radio about 5–3 meters, 60–110 MHz)

With KW and VHF there is an overlapping of terms when using the word band, since the shortwave and sometimes also mediumwave and VHF range are divided into different meter bands. With VHF there is a division into frequency bands which are named depending on their frequency and the standard broadcast:

• VHF, MW and SW meter tapes, 160 to 2 meter tape, (example: tropical tape the 120 meter tape ),
• VHF bands CCIR band (87.5–108 MHz ) and OIR band (65.8–74 MHz) and the so-called Japan or Japanese band (76–90 MHz), with TV the individual subordinate bands were also included marked with the Roman numerals I - V.

At the time when Marconi, Popow, Branly, Ducretet, Baviera and other pioneers were sending signals, there was initially no possibility of choosing an appropriate transmission or reception area. There were no components that could set a range or a desired wavelength or frequency for transmission. Only when the resonant circuit began to be equipped with variable coils could the intended range of wavelength or frequency be determined by changing different coils or groups of coils on the receiver side. Transmitter-side coils differed considerably from those in the receiver. The ones in radio transmitters are much larger in their dimensions, and repositioning of transmitter coils was never possible, since a radio station always broadcasts in one frequency or wavelength. This also applied when the same program was broadcast on a second frequency of the radio station. A quality factor in the manufacture of coils was the choice of materials as well as the technical requirements and the precision with which the coils were wound, both for the transmitter-side in radio houses, the receiver-side by radio equipment manufacturers and for the self-assembly of receivers by radio amateurs.

When using a receiver-side pair of two or more coils matched to one another, a change in their position relative to one another, such as rotating the coils relative to one another, made it possible to select a specific individual transmitting station. Various mechanisms have been developed for this, for example tilt and swivel couplers or a variometer . The later use of a wave (switch) switch made it possible to switch between the coils or coil groups connected to it - which were adapted for the corresponding wave ranges. Changing by plugging and unplugging was no longer necessary. Apart from the invention of an adjustable feedback on the receiver side , the innovations of a slider on the coils and the aforementioned variometer, but above all variable capacitors , for example the rotary capacitors, were an even more precise way of setting the wavelength or frequency.

organization

Frequency and wave plans

With the increase in the number of broadcasting stations and mutual interference, it became necessary to regulate the use of wavelengths or frequencies and their ranges across borders. The first agreements were also made about the respective use of the wavelengths. The first global agreement on an international assignment of frequencies for radio stations in the medium and long wave ranges used at that time took place during the Washington International Radiotelegraph Conference in 1927. A standardization similar to the later television standards was not carried out for the time being.

control

The control of the radio had a major influence on the development of radio. It had a very different effect in individual countries around the world, from accelerating to braking. The reason for the different distribution of broadcasting in terms of station and listener numbers in the USA compared to Europe was primarily the noticeably different level of surveillance and control. The most important thing was that overseas there was no state monopoly on radio or radio, as in many European countries, and that there were also no state-distributed receiving licenses. Monopoly already meant when at least one component of the radio, transmitter or program, i.e. either the companies that set up or operate broadcast technology or the program and other broadcasting companies, was state-owned or the majority on the supervisory boards of the respective companies was state-owned was controlled. In addition to the transmitter side, there were massive controls in several European countries over who, where and with what could be received.

In the USA, for example, receiver-side regulations were not even mentioned in the two “ Radio Acts ” of 1912 and 1927 enacted by the Department of Commerce . There were no rules about program content either. The main content included provisions under which conditions, mostly just technical details such as frequency and interference radiation regulations, private people were allowed to operate a radio transmitter with a program. The following examples illustrate the difference between overseas and Europe. While in the USA a government agency, the National Bureau of Standards assigned to the Department of Commerce , issued a document Construction and Operation of a very simple radio receiving equipment on March 16, 1922 - a construction manual for self-assembly for an inexpensive radio receiver including antenna for a material price of 10 up to US $ 15 - was being discussed at the Ministry of Post in Germany at the same time about the permission of only communal reception, the so-called hall radio. According to this view, not even licenses for reception to private listeners should be issued. The discussions of the German ministries for the Reichswehr and -post about the approval of the broadcasting culminated in a dispute with the accusation "abuse of army equipment", because the military believed, because of the on its behalf u. a. Tests carried out by Hans Bredow on radio transmissions in trenches , also to have the monopoly over the radio and over the civil use of the parts of the military radio technology still available from the world war. In this context, the former German and Austrian an estimated 100,000 intelligence soldiers of the First World War, despite their technical competence, were excluded from a democratic say in the design of future radio in their home countries Germany and Austria.

In addition, US broadcasting is largely privately owned and funded from the start. Another noticeable difference to Europe was that broadcasting in the USA had a much more regional character. In the early years, there were not even nationwide stations like the later NBC, for example, whereas in Europe national state or public broadcasters or broadcasters began broadcasting through contracts with state institutions. The only state or state-controlled broadcasting facilities in the USA are the worldwide military network of the AFN and a national broadcaster that broadcasts parliamentary sessions as television programs.

The unique Dutch so-called "pillar model" is an exception or special position . The model, which is more liberal on a European scale, has lasted from its beginnings in 1924 to the present day. In spite of the existing state censorship and a statutory broadcasting time regulation, several strongly competing associations with a church or other political background organize radio in this country very independently. Initially they rented transmitters, later they also built them themselves, e.g. B. Hilversum 2 .

Tables

International distribution

Note: This table shows a selection of the international distribution of radio broadcasting up to 1945. The selection is limited by the fact that the respective first radio activity for a country or mandate area or a colony etc. is listed. If a country carries out other world-class activities (premieres), such a country can be named several times. Channels from the same continents are marked with the same colors.

Country / State	Trial / amateur operation from:	Sender or founder	commercial operation from:	code	note
Test transmitter
Denmark	1904	V. Poulsen	-	-	First voice transmission
United States	1906	R. Fessenden	-	-
Great Britain	1907	Royal Navy	-	-	First program broadcast from a ship, Chatham, Kent
Regular program operation
United States	1909	Doc Herrold 6XF	1921	KQW	First news transmitter / continuous operation from 1909
United States	1916	Dr. Conrad 8XK	1920	KDKA	First full program transmitter / continuous operation from 1916
Denmark	1917	Poulsen / Dan. post Office	1923	OXZ	Marine radio
Netherlands	1919	Steringa Idzerda	1919	PCCG	Full program broadcaster, first radio in Western Europe
Canada	1919	XQA	1920	CFCF
German Empire	1919	Eberswalde	none	C. Lorenz AG transmitter	↑ see also: Versuchsfunkstelle Eberswalde
German Empire	1920	Königs-Wusterhsn.	none	Sender of the Reichspost	↑ see also: Funkerberg
Argentina	1921	Radio Argentina	1921	LRO
Uruguay	1922	Radio Montevideo	1922
France	1921	Ducretet / Branly and PTT Paris	1922		Name of the first program station: Radio Tour Eiffel (PTT) and Radiola (SFR-P)
Great Britain	1922?	BBC Hull	1922	2LO
New Zealand	1921	Radio Dunedin / Otago	1922	DN / 4XD	University broadcaster, 4XD was a non-commercial volunteer broadcaster from 1922 to 1990 . First radio station in Oceania .
Switzerland	1922	Airfield broadcasters in Bern and Lausanne	1922		Business news, test broadcasts, music, news. First commercial radio in Central Europe
Chile	1922	Radio Chilena	1922
Cuba	1922	Luis Casas Romero	1922	2LC / PWX	Rádio Sociedade de Cuba
Soviet Russia	1922	Москва-Лапа	1924	LM (ЛМ)	Long wave at 3000 meters
Belgium	1922	Georges De Caluwé	1924		Radio Antwerp ("Radio Kerkske" / little church) First shortwave transmitter
Austria	1923	Oskar Koton (Company Czeija & Nissl) Radio Hekaphon	1923		Program with voice and music broadcasts
ČSR	1923	Radioslava Prague station	1923		Program company: Radio Journal
Spain	1923	Radio Iberica	1923		0.5 kilowatts
Netherlands	1923	Hilversum Seintoestellen Fabriek	1923		↑ see also: Hilversumsche Draatlooze Omroep
Republic of China	1923	Harbin	1923		Radio Corporation of China. Owned by RCA First English language broadcaster in China
German Empire	1923	Funk-Hour Berlin Transmitter of the Funk-Hour AG Berlin in the Vox house	1923		0.25 kilowatts, subsidiary and first transmitter of the German hour company
Denmark	?	Poulsen / Dan. post Office	1924	OXE	Music broadcasts
Austria	1924	RAVAG Radio Vienna	1924
Portugal	1924	Abílio Nunes Dos Santos	1925	P1AA	Radio Lisboa
Japan	1923	Tokyo Station	1925	JOAK	First national language broadcaster in Asia
Ceylon	1923	Colombo Radio	1925
Norway	1923	Kringkasting selskapet	1925		Oslo
Sweden	1925	AB Radiotjänst	1925
Denmark	1925	Danmarken radio	1925	DR	3 times a day
Finland	1923	Suomen Yleisradio AB	1926	OY
Italy	1924	URI	1924		Unione del Radiophonica Italiana
Yugoslavia (Kingdom)	1924	Radio Beograd-Rakovica	1924		First transmitter on the territory of the former Yugoslavia , ↑ see also: Radio Belgrad
Hungary	1925	Budapest I	1925		Magyar Telefonhírmondó és Rádió ↑ see also: Magyar Rádió
Poland	1925	Radio Warsaw	1925
Latvia		Latvijas radio	1925
Ireland	1925	Radio Dublin	1926	2RN
Croatia	1926	Radio Zagreb	1926		↑ see also: Hrvatska Radiotelevizija
Free City of Gdansk	1926	Transmitter Gdansk	1926		Program takeover from ORAG
Lithuania	1926	Radio Kaunas / Radio Kovno	1926		First Lithuanian-speaking broadcaster in Kauen
Poland	1927	Polskie Radio Wilno	1927		First Polish-language broadcaster in Vilnius (then part of the Second Republic of Poland )
Romania	1927	Radio Bucureşti	1928		Asociaţia Prietenilor (Society of Friends of Radiotelephony) Radiotelefoniei was an amateur business from 1927 , and the Societăţii de Difuziune Radiotelefonic became a commercial business from 1928
China	1928	Nanjing	1928	XKM	Central Broadcasting Systems First Chinese language broadcaster in China
Slovenia	1928	Radio Ljubljana	1928
Morocco		Radio Maroc	1928		First transmitter in Africa, operator: Société Nationale de Radiodiffusion
USSR	192?	Radio Moscow	1929		First international broadcaster with broadcasts in foreign languages ​​a. a. in German, was used for propaganda information about the USSR. 1991 renamed Voice of Russia
Iceland	1929?	Ríkisútvarpið Reykjavík	1930		Ríkisútvarpið RÚV (Icelandic National Broadcasting Service)
Vatican	1931?	Radio Vaticana	1931		International broadcaster
Italy	193?	Radio Bari	1932		First Arabic-speaking radio station in Europe, a propaganda station operated from Bari during the reign of Benito Mussolini , particularly for the Middle East and North Africa
Egypt	193?	Radio Cairo	1934		First state broadcaster in Egypt
Ethiopia	?		1935		Ethiopian Radio Agency
League of Nations mandate for Palestine	193?	Ramallah transmitter	1936		Palestine Broadcasting Service in English, Arabic, etc. Hebrew
Kingdom of Iraq	193?	Baghdad radio	1937
Moldovan ASSR	193?	Radio Tiraspol	1937		Propaganda transmitter of the USSR in the former Moldavian Autonomous SSR in Tiraspol , today Transnistria
Greece	193?	Radiophonikos Stathmos Athinon	1938		↑ see also: Elliniki Radiofonia - Athens
Albania	1938	Radio Shqiptar	1938		built as a propaganda transmitter for the Italian occupying forces, used and expanded by Albania after the war
Andorra	193?	Radio Andorra	1939		Radiophonie du Midi
Monaco	194?	Radio Monte Carlo	1943		Propaganda station of the German foreign broadcasting company Interradio AG
North Macedonia	1944	Radio Skopje	1944		↑ see also: Skopje
Montenegro		Radio Cetinje	1944		↑ see also: Radio Montenegro
Kosovo		Radio Pristina	1944		↑ see also: Radio and television in Yugoslavia

Distribution of German-speaking channels

Note: This table shows the distribution up to 1945 - of German-speaking channels or broadcasts from German-speaking countries and non-German-speaking countries.

See also : History of Radio in Germany , History of Radio in Austria and History of Broadcasting in Switzerland

City / state part / canton	Trial / amateur operation from:	Channel	commercial operation from:	Note / achievement / founder
Eberswalde./Preussen	1919	Eberswalde on the Finow Canal , Lower Austria of Berlin, private test transmitter of C. Lorenz AG , Radio Lorenz, Eberswalde	none	Regular test operation until 1939, then dismantling and conversion ↑ see also: Eberswalde radio station
Bel-Air near Geneve	1920	Transmitter Genève / Geneva- Bel Air	- "-	League of Nations transmitter from 1920 to 1921, relocation to Bern-Münchenbuchsee
K.-Wusterhsn./Preussen	December 24, 1920	Königs-Wusterhausen near Berlin, transmitter of the Deutsche Reichspost	- "-	Test operation until 1926 ↑ see also: Funkerberg
Bern	September 9, 1921	Transmitter Bern- Münchenbuchsee	- "-	10 kilowatts, League of Nations transmitter
Basel / Basel-City	1920	Several channels: Zeughaus in St. Jakob / Basel and in the Bernoullianum	- "-	Hans Zickendraht
Lausanne / Vaud (Vaud)	October 1922	Airport broadcaster Lausanne Program company Utilitas or, from July 1922, Broadcasting Romand , foundation of Utilitas and Lausanne radio club.	February 26, 1922	Identification: LB2 pilot weather & aircraft briefings, from October 1922 in the test and from February 1922 regularly in the evenings music, news with weather & sports. First commercial radio in Central Europe.
Bern	April 26, 1922	Transmitter Bern- Münchenbuchsee	June 1923	Business news
Vienna	April 1, 1923	Radio Hekaphon , private test transmitter	July 1, 1923	100 watts, Oskar Koton (company Czeija & Nissl), designed mixed program.
Berlin	1923	Funk-Hour Berlin Transmitter of the Funk-Hour AG Berlin in the Vox house	October 29, 1923	0.25 kilowatts, subsidiary (like all 8 other Reich German regional AGs) of the company Deutsche Stunden mbH
Kloten / Zurich	September 1923	Airfield transmitter Kloten - Dübendorf .		1 kilowatt, the radio tests were carried out by the Zurich Radio Club
Geneve	1922?	Genève- Cointrin airport transmitter	x. 1923 (month unknown)	Identifier: LB1, program like Lausanne, later merger of the two broadcasters by the Société Romande de Radiophonie (founded December 17, 1923).
Leipzig / Saxony	1924	Leipzig, transmitter Alte Waage , antenna Neues Johannishospital	March 2, 1924	Mitteldeutsche Rundfunk AG / German hour
Munich Bavaria	1923	Munich, broadcasting hall in the Ministry of Transport, Arnulfstrasse	March 30, 1924	0.25 kilowatts, German hour Bavaria / German hour
Frankfurt am Main.	1924	Frankfurt am Main	April 1, 1924	1.5 kilowatts, Südwestdeutsche Rundfunkdienst AG / German hour
Hamburg / Hanseatic City	1924	Hamburg, Sender Fernsprechamt Schlueterstrasse	May 2, 1924	0.7 kilowatts, Nordische Rundfunk AG / German hour
Stuttgart / Württemberg	1924	Stuttgart	May 11, 1924	0.25 kilowatts, Süddeutsche Rundfunk AG / German hour
Breslau / Prussia	1924	Wroclaw	May 26, 1924	Radio hour Silesia / German hour
Münster / Prussia	1924	Muenster	May 26, 1924	0.7 kilowatts, West German radio hour / German hour
Königsberg / Prussia	1924	Königsberg, Pregelwiesen transmitter	June 14, 1924	0.5 kilowatts, Ostmarken Rundfunk AG / German hour
Vienna	1923	Radio Vienna Stubenring	October 1, 1924	350 watt RAVAG
Zurich	1923	Zurich- Höngg Radio Zurich station	October 23, 1924	approx. 0.5–1 kilowatts Operator: Radiogenossenschaft in Zurich
Basel	1924	Basel- Sternenfeld airfield transmitter	1924	Music pilot weather aircraft briefings
Bern	1925	Transmitter Bern- Münchenbuchsee Radio Bern	November 19, 1925	approx. 1.2 kilowatts Operator: Radiogenossenschaft Bern
Königs-Wusterhsn / Preu.	1926	Germany station I	January 7, 1926	20 kilowatt long wave Deutsche Welle GmbH
Vienna	1926	Transmitter Vienna- Rosenhügel	January 30, 1926	7 kilowatts RAVAG
Gdansk / Free State	1926	Transmitter Gdansk	June 1, 1926	Program takeover from ORAG Königsberg
Basel	1926	Basel-Sternfeld airfield station, later the Zeughaus station in St. Jakob Radio Basel	June 19, 1926	Operator: Radiogenossenschaft Basel
Innsbruck / Tyrol	1927	Transmitter Innsbruck - Aldrans	June 2, 1927	RAVAG
Linz / Upper Austria	1927	Transmitter Linz - Freinberg	June 24, 1928	RAVAG
Zeesen / Prussia	1926	Germany transmitter II	August 26, 1929	8 kilowatt shortwave radio station Moscow from 1929
Moscow / RSFSR	192?	Radio Moscow	1929	International station "Radio Moskwa" in German
Vatican	193?	Radio Vaticana	1936	First broadcast in German
Mělnik / Bohemia	1938	Mělník transmitter	May 1, 1938	First German-language broadcaster of Radioslava / Radiojounal in CSR 140 kW
Great Britain		BBC ( BBC World Service )	?. 9th 1938	German-language service of the BBC (discontinued in 1999). It is worth mentioning programs during the Second World War such as Mrs. Wernicke : Comments from a "Volksjenossin"
Vaduz	1938	Vaduz transmitter	October 15, 1938	First transmitter in Liechtenstein
Belgium	1945	From 1961 first own transmitter in Liège	October 1, 1945	First German-language broadcast on the Belgian radio

Public honors

criticism

As an example: commemorative stamp for 100 years of radio with a picture of Guglielmo Marconi

In the public consciousness, Guglielmo Marconi, important for telecommunications and a. with his distance records of wireless telegraphy connections, often attributed to the invention of the radio. The telegraphy technology company Marconi of his family also contributed to Marconi's fame. In addition to telegraphy transmitter and receiver technology, they also produced and sold technology with the same function for radio. The latter, however, mostly only from the 1920s.

G. Marconi applied for a British patent - only by filing text documents - in June 1896 (which was granted to him with the number 12039 for " Transmitting Electrical Impulses and Signals, and an Apparatus therefor " on July 2, 1897). However, he only added the explanatory visual documentation with drawings required for this in March 1897, after a year had passed since Popov's 250 m attempt.

And during his first transatlantic radio attempt in 1901, he only sent an S in the form of a Morse code by typing in the 3 short signals: · · · , so no z. B. Sound signal similar to Popow's experiments.

Who succeeded in the first experimental transmission of sounds before Poulsen's method of arc technology is not yet known or cannot be clearly proven. In addition, it is hardly possible to attribute the invention of the radio to one person, since no one could do without inventions by others in order to be successful himself, which applies to all pioneers.

This was evident, for example, when using the various coherers or Edison's phonograph or when working together directly, such as B. Marconi with Ferdinand Braun , who brought them the Nobel Prize for Physics in 1909 for their achievements "in recognition of their contributions to the development of wireless telegraphy" . It should be added that the latter u. a. developed the inductively coupled antenna circuit with Adolf Slaby , another German radio pioneer.

In addition, around 1900 there was still no clear definition of the term radio and its demarcation from telegraphy. At that time, the word radio was still used for all wireless broadcasts (↑ see also: Section of this article below, use of the term radio ).

1943 chose the United States, the Supreme Patent Court of the United States that Tesla was the inventor of radio. This ignored not only the contribution of the Russian scientist Alexander Popow, but also, above all, other achievements made in Europe by Poulsen, Hughes, Branly, Bavieras, but also by the American Greenleaf Whittier Pickards , without whose extensive tests and inventions no usable detector receiver would be available would have stood.

Honors from the IEEE

The International Institute of Electrical and Electronics Engineers (IEEE) published a list of historical achievements, calling them milestones in electrical engineering and electronics. The following personalities will be honored for their achievements especially in the area of ​​the development of wireless transmission technology.

• Edouard Branly
• Alexander Stepanovich Popov
• Guglielmo Marconi
• Valdemar Poulsen
• Ernst FW Alexanderson
• John Ambrose Fleming
• Reginald Aubrey Fessenden
• Frank Conrad

The term radio

(↑ see also: content-related section, criticism above )

The term radio stands or stood for different terms depending on the time and regional usage . B. for the unambiguous answer the question is when or by whom the invention took place.

Initially, in the late 19th and early 20th centuries, the term global stood for

• a broadcasting station or station,
• as an abbreviation for the receiving device or
• generally for wireless broadcasting, as well as for telegraphic and radio signals
• Name of the medium.

This is particularly true in the English-speaking world to the present day. From the 1920s onwards, only the radio segment was designated as broadcast (ing) .

In German or as a respective expression in other West Germanic languages , the words Rundfunk (later radio ) or especially in German-speaking Switzerland, in Liechtenstein and partly in Austria Rundspruch as well as in Flemish or Dutch Omroep ( roep = call) emerged.

In Romance as well as in Slavic languages , the root word radio (f-ph) on ... or radiotelephon ... plus the respective ending in the corresponding language is used.

According to the Duden, the word is defined as follows:

"Quote:

• 1. Radio, radio receiver
• and 2.
  • Broadcasting, radio (as the device embodied by the radio device for transmitting speech and sound performances)
  • Transmitter, broadcaster "

- Entry in "Duden - German spelling"

Individual evidence

1. ↑ Werner Faulstich: Introduction to media studies . Wilhelm Fink Verlag, Munich 2002, ISBN 3-7705-3799-8 , pp. 24 and 167-204.
2. ↑ Petra Löffler, Albert Kümmel: Media Theory 1888-1933 . Suhrkamp Verlag, Frankfurt am Main 2002, ISBN 3-518-29204-8 , pp. 156-311.
3. ^ Raoul H. Francé: Bios The Laws of the World Volume II. Walter Seifert Verlag. Stuttgart-Heilbronn, 1923. p. 42.
4. ↑ Dieter Bäuerle: Laser: Fundamentals and applications in photonics, technology, medicine and art . Wiley-VCH Verlag. Weinheim, 2009. p. 11 ff. ISBN 978-3-527-40803-0 .
5. ↑ Jed Z. Buchwald: The creation of scientific effects . University of Chicago Press. Chicago, 1994. ISBN 0-226-07888-4 , pp. 218 ff.
6. ↑ ^{a b} Degna Marconi: Chapter Three. In: My Father, Marconi. Frederick Muller, London 1962.
7. ^ Thomas Piper: Prof. DE Hughes' Researches in Wireless Telegraphy. In: "The Electrician". May 5, 1899. London 1899, pp. 40-41.
8. ^ ^{A b} Fred Gardiol, Yves Fournier: In: Salvan, the cradle of telecommunications. Marconi and his first attempts at wireless communication in the Swiss Alps. (PDF; 486 kB) , Bulletin SEV / VSE 21/2007, pp. 24–28.
9. ↑ Hugh GJ Aitken: Syntony and Spark . Princeton University Press. Princeton (NJ), 2014. pp. 125ff. ISBN 978-1-4008-5788-3 .
10. ↑ Guigliemo Marconi: Wireless telegraphic communication - Nobel Lecture, December 11, 1909: Publications of the Nobel Foundation 1909, accessed at nobelprize.org
11. ↑ Ángel Faus Belau: Historia de la Radio . Taurus Ediciones, Madrid 2007.
12. ^ F. Fuchs: Grundriß der Funken-Telegraphie . R. Oldenbourg, Munich / Berlin 1922, p. 58.
13. ^ F. Fuchs: Grundriß der Funken-Telegraphie . R. Oldenbourg, Munich / Berlin 1922, p. 57.
14. ↑ Bureau of Standards : Radio communication pamphlet № 40. The Principles Underlying Radio Communication . Signal Corps, US Army. War Department. Document № 1069. Washington, 1922. p. 400.
15. ^ Poulson wireless progressing. In: "Popular Mechanics". June 1907 issue. Published by Hearst Magazines. Chicago, 1907, p. 675.
16. ↑ Frank Sichla: Reception principles and receiver circuits . VTH-Verlag, Baden-Baden 2009, ISBN 978-3-88180-842-2 , pp. 9-12.
17. ↑ Maurice L. Sievers. Crystal-clear detection. In: Crystal-clear. Volume I. Sonoran Publisher, Mesa (Arizona USA) 2008, ISBN 978-1-886606-01-2 , p. 3 ff.
18. ↑ Gregory Malanowski: The cat-whisker. In: The race for wireless. Author House. Bloomington (Indiana USA) 2011, ISBN 978-1-4634-3750-3 , pp. 45 ff.
19. ↑ Vladimir Gurevitch: Electric relays: Principles Applications. Taylor & Francis Group / CRC Press, Boca Ratin (Florida USA) 2006, ISBN 0-8493-4188-4 , pp. 211 ff.
20. ↑ Thomas H. Lee: Planar Microwave Engineering: A practical guide to theory, measurements and circuits. Cambridge University Press, Edinburgh 2004, ISBN 0-521-83526-7 , p. 297 ff.
21. ^ GWA Drummer: A concise history of audio and sound reproduction. In: Electronic inventors and discoveries. Taylor & Francis Group / Institute of Physics Publishing, Bristol 1997, ISBN 0-7503-0493-6 , p. 18 f.
22. ↑ publications radiomuseum.org RMorg
23. ^ Swiss Radio DRS, collective of authors: History of the radio 1911–2008 . Schweizer Radio DRS, Zurich 2008, p. 6.
24. ^ Kurt Seeberger: The radio. In: Wolfgang Stammler: German Philology in Outline . Volume III. Berlin, 1957, Col. 666.
25. ^ "Popular Mechanics" , June 1907, ibid.
26. ↑ Publication by the “Radio Museum” association, ibid.
27. ^ Wolf-Dieter Roth: Pirate transmitter . Siebel Publishing House. Baden-Baden, 2004. p. 105. ISBN 3-88180-637-7 .
28. ↑ The latest in radio telephony. In: morning edition “Neue Freie Presse” , March 21, 1914, editor Moriz Benedikt. Vienna, 1914, p. 9.
29. ^ Johann Richter: The glaciation of the Belt Sea and the southern Baltic Sea in the winter of 1928–1929 . Reprint from 1933. Salzwasser Verlag, Paderborn 2011, ISBN 978-3-86444-069-4 , p. 7 f.
30. ^ Gerd Klawitter: 100 Years of Radio Technology in Germany , Volume 2. W&T Verlag. Berlin, 2005. pp. 85ff. ISBN 3-89685-511-5 .
31. ↑ Publication by Jorge Guimarães Silva Lisbon ( Memento of February 18, 2012 in the Internet Archive )
32. ^ Brian Hennessy: The Emergence of Broadcasting in Britain Southerleig, Devon 2005, ISBN 0-9551408-0-3 , p. 11 f.
33. ↑ oldtimeradio.de: Broadcasting history - until 1920
34. ^ Association "Radio Museum": preliminary stage of broadcasting
35. ↑ Publications from Columbia Broadcasting System CBS ( Memento September 20, 2010 in the Internet Archive )
36. ↑ Joseph E. Baudino, John M. Kittross: Milestones: Westinghouse radio. In: Journal of Broadcasting. 1977. (online)
37. ^ Radio Society of Great Britain: The Wireless World and Radio Review . Iliffe & Sons. London, 1929. p. 54.
38. ^ Hugo Rössner: Course book of the ether . Radio world. Wiener Radio Verlag. Vienna, 1924.
39. ^ Mike King: Canada's first radio station goes off the air. In: "The Gazette". January 29, 2010, Postmedia Network, Montreal 2010 “The Gazette” @ montrealgazette.com
40. ↑ Published in: Festschrift 75 Years Lorenz AG - 1880 to 1955. Verlagdruckerei Conradi & Co., Stuttgart 1955.
41. ↑ Joseph E. Baudino, John M. Kittross, ibid. (Online)
42. ↑ ClarinX publications: La historia de la radio en la Argentina
43. ↑ Jim Sullivan: Dashing heroes of a harbor crossing. In: Orago Daily Times. December 6, 2008, accessed February 14, 2019 . 
44. ^ Caroline Ulmann-Mauriat: The birth of broadcasting in France. In: The idea of ​​the radio. in the yearbook Media and History 2004. UVK Verlagsgesellschaft, Konstanz 2004, ISBN 3-89669-462-6 , p. 112 f.
45. ↑ Barry Mishkind: Research list of stations of the USA list
46. ^ FIFA Online: The roots of football coverage . FIFA publications
47. ↑ ^{a b} Caroline Ulmann-Mauriat, ibid.
48. ^ Peter Lord: The history of Hull's first radio station . BBC Publications 2010 (online)
49. ^ Publications of the German Broadcasting Corporation in Switzerland DRS2
50. ↑ О нас . Voice of Russia publications Voice of Russia , accessed October 22, 2013.
51. ^ Publications of the Japan Broadcasting Corporation NHK ( Memento of November 12, 2009 in the Internet Archive )
52. ^ Publications Colombo Radio Colombo Radio
53. ^ Dennis D. McCarthy, Kenneth P. Seidelmann: Time: From Eart Rotation to Atomic Physic . Wiley-VCH, Weinheim 2009, ISBN 978-3-527-40780-4 , p. 287.
54. ↑ Holger Lersch: Aspects of a comparative radio history. In: The idea of ​​the radio. In: Yearbook Media and History 2004. UVK Verlagsgesellschaft, Konstanz 2004, p. 38.
55. ↑ Helmut Schanze : Broadcasting, Medium and Masses. In: The idea of ​​the radio. In: Yearbook Media and History 2004. UVK Verlagsgesellschaft, Konstanz 2004, pp. 18–19.
56. ^ Silke Merten: The media system of the Netherlands . Publications of the University of Münster, 2005. University of Münster
57. ^ Wolf-Dieter Roth: Pirate transmitter , ibid.
58. ↑ Dashing heroes of a harbor crossing "Otago Daily Times" Sept. 6, 2008 Otago Daily Times
59. ^ Publication of Radio Cubana RC ( Memento of October 13, 2012 in the Internet Archive )
60. ↑ Слушайте! Говорит Москва! Voice of Russia publications Voice of Russia , accessed October 22, 2013.
61. ↑ Publication of Zeezenders ( Memento from November 9, 2012 in the Internet Archive )
62. ↑ Lenka Cábelová: The beginnings of broadcasting in Czechoslovakia. In: The idea of ​​the radio. in the yearbook Media and History 2004. UVK Verlagsgesellschaft, Konstanz 2004, ISBN 3-89669-462-6 , p. 139 ff.
63. ^ Toby Miller: Television: Critical Concepts. In: Media and Cultural Studies. Routledge Publishing, 2003.
64. ^ Jorge Guimarães Silva: Portugal data . Portugal ( Memento of April 21, 2012 in the Internet Archive )
65. ^ Publications of the Norge Radio NRK
66. ↑ publications Radio Sverige RSV
67. ↑ publications Danmarken Radio DR ( Memento of June 2, 2013 Internet Archive )
68. ^ Publications of Suomi Radio SuR
69. ↑ Publications of the Vatican Radio Vatican ( Memento of April 5, 2013 in the Internet Archive )
70. ^ Releases from Latvijas Radio LTR
71. ↑ Publications of RTE RTE-1920
72. ^ Publications by RTE RTE-history
73. ↑ Alexander Ganse: Free City of Danzig, 1920–1939 2002, publications by the Korean Minjok Leadership Academy KMLA
74. ↑ Publications by Lietuvos nacionalinis radijas ir televizija LRT ( Memento from January 9, 2019 in the Internet Archive )
75. ↑ Sigitas Žilionis: 4 March 1927r. w Wilnie nadana pierwsza Audycja Radiowa S. Zilionis
76. ^ Publications of Radio Romania RR-1927
77. ^ Ibid: RR-1928
78. ↑ Toby Miller, ibid.
79. ↑ Publications by Broadcasting Corporation of China BCC ( Memento of May 14, 2007 in the Internet Archive )
80. ^ Ibid: Radio Vatican ( Memento from April 5, 2013 in the Internet Archive )
81. ^ Publications by Radio Maroc RM
82. ↑ О нас . Publications of the Voice of Russia. ibid.
83. ^ Releases from Radio Iceland RÚV
84. ↑ Publications of the Vatican Radio Vatican ( Memento of April 30, 2013 in the Internet Archive )
85. ^ Keith Neilson, Greg Kennedy The British Way in Warfare: Power and the International System, 1856-1956 . Farnham, England, 2010, ISBN 978-0-7546-6593-9 , p. 65.
86. ^ Douglas A. Boyd. Broadcasting in the Arab World. Philadelphia, Temple University Press. 1982.
87. ↑ Publications by Ethiopian Radio and Television Agency ERTA ( Memento of October 27, 2012 in the Internet Archive )
88. ^ Publication by Radio Israel Int. israelradio ( Memento from March 21, 2012 in the Internet Archive )
89. ↑ Yeheskel Kojaman: Jewish Role in Iraqi Music . Journal of Babylonian Jewry In: " The Scribe ", Issue 78 2005/10 Published by the Exilarch's Foundation, 2005, p. 42.
90. ↑ Kiesinger - Irresistible Power. In: “Der Spiegel” magazine , issue 49/1966, November 28, 1966, Spiegelverlag Hamburg 1966.
91. ^ Publication by RTV Montenegro RTCG
92. ↑ Markus T. Drack: Radio and television in Switzerland. Verlag Hier + Jetzt, Baden 2000, ISBN 3-906419-12-6 , p. 52.
93. ^ Jean-Jacques Lagrange: 1922-1930: Les balbutiements. In: Mon Histoire de la Radio Suisse Romande. notreHistoire.ch , 2012, accessed on September 28, 2014 ( French )
94. ^ Publications of the Radiomuseum Lucerne Foundation ch-radiomuseum
95. ↑ Markus T. Drack: ibid. '
96. ↑ Jean-Jacques Lagrange: ibid.
97. ↑ ibid: ch-radiomuseum
98. ^ Roger Jean Rebmann: Beginnings of Basler Rundfunk and Studio Basel. In: Altbasel.ch. March 24, 2017, accessed on February 14, 2019 (with additional sources). 
99. ↑ ibid: ch-radiomuseum ch-radiomuseum
100. ↑ Lenka Cábelová, ibid, p. 160 f.
101. ^ Marie Gillespie, Alban Webb: Diasporas and Diplomacy: Cosmopolitan contact zones at the BBC Worldservice (1932–2012) . Routledge, Abingdon-Oxon 2013, ISBN 978-0-415-50880-3 , p. 57 ff.
102. ^ Publication by the Belgian Broadcasting Corporation BRF ( Memento from August 16, 2014 in the Internet Archive )
103. ^ List of IEEE Milestones . IEEE publications , accessed October 24, 2013.
104. ↑ Duden - German spelling entry radio )