radio
Radio ( Latin radius , beam ') as a short word for radio or radio broadcast receivers referred to an apparatus for reception of radio broadcasts . With conventional radios, these are transmitted by a radio transmission system using terrestrial transmission (such as aerial television ) using electromagnetic waves or as high-frequency electrical signals via broadband cables (such as cable television ). The information received is essentially converted into sound ; To a small extent, the broadcast signal can also contain data and information, such as the RDS data, which make it possible, for example, to transmit the station name.
In addition to a radio receiver, radio can be received with special extensions, additional devices, USB sticks , computer programs or suitable model series, for example from:
- Computers ( streaming audio , internet radio ),
- audiovisual players ( cassette recorders , CD and DVD players ) and televisions
- Mobile phones ,
- Clocks and
- Toys
as well as with
- analog and digital satellite or receivers for cable television and
- digital receivers of various reception technologies such as SDR or Digital Radio Mondiale (DRM), DAB , HD radio and other DVB processes
be received.
Use of language
Historically, at the beginning of broadcasting in Germany, the terms “radio”, “ radio ” and “ broadcasting ” competed . In 1924 letters from the Austrian authorities said “Broadcasting” in brackets after radio. The Reichspostverwaltung in Berlin rejected the buzzword "radio". Radio is nothing more than a beam. At that time, the Reichspost acted as a language guardian. For example, she banned the words “poste restante” and “returned letter” from her correspondence. So your vote against the word radio carried weight.
It is called the radio in communal German , derived from the radio device. In central and northern Germany it is always a neuter. In southern Germany, in Austrian German and Swiss High German , the radio is also common, derived from the radio.
In addition, both in German-speaking countries and in global usage, the word “radio” denotes a radio or radio station or a broadcasting chain such as B. Radio Bremen , Swiss radio and television or Radio Canada International . The short form “radio” is always neuter in this meaning until a compound is formed that requires something else (such as “the radio station”).
Classification as a radio receiver
In Germany, a radio is a radio receiver within the meaning of the German State Treaty on Broadcasting Fees , i. H. a "technical device that is suitable for wireless or wired, non-time-shifted audio or visualization or recording of radio performances (radio and television)."
history
In German-speaking countries, radio operations began in Switzerland and Germany in 1920 with test broadcasts, the first regular program broadcasts followed in late 1922 and early 1923 by two Swiss airfield stations, in autumn 1923 with the Reich German radio hour in Berlin and in October 1924 with the Austrian RAVAG in Vienna . The location of the first imperial German radio broadcasts was the first recording studio in Germany, today's old building studio of the Berlin University of the Arts in Berlin.
Analog radio reception
Development of receiving devices
Start time
In the early years, the technology of analog receivers was unaffordable for a large part of the population. However, by building a detector receiver, for example, the reception of local transmitters was also possible for poorer sections of the population. Last but not least, after the First World War there was a large number of deactivated military radio operators around the world who not only had technical experience with receivers, but also demanded a say in the development of future radio. In Germany alone there were around 100,000 former military radio operators.
On December 22nd, 1920, the first public radio transmission of a Christmas concert took place in the German Reich ( Weimar Republic ) by the Königs Wusterhausen station of the Reichspost . This event was an important milestone in the development of public broadcasting in Germany .
At the end of the 1920s, thanks to new production methods, tube radios in particular were offered at significantly lower prices. The first widespread device in German-speaking countries was the OE333 local receiver produced by Audion for five years from the then Loewe-Audion GmbH (previously Radio Frequency Loewe ) in Berlin-Steglitz , presented at the radio exhibition in 1926. Because of the modern methods, Siegmund Loewe is in the English-language literature described as "German Henry Ford ". The OE333 cost 36.50 Reichsmarks including the 3NF triple triode (comparable to the later ECC83 ). Only the corresponding antenna coil made of wire had to be bought.
In order to reach all sections of the population more effectively with the National Socialist propaganda , the Volksempfänger was developed in 1933 and presented by the Reich Minister for Public Enlightenment and Propaganda in August 1933 . The device cost about half as much as the radios available in Germany until then. It was a simply constructed device that was sold at a price of 76 Reichsmarks (adjusted for inflation, equivalent to 349 euros in today's currency).
High-quality radio sets were equipped with a push-pull output stage . To simplify the choice of station, there were a few device models with an automatic, motor-driven station search and several so-called station buttons for switching between stations that were frequently heard, even before the Second World War . The development of car radios also began before the war in Europe and overseas, but they hardly played a role in the market because they were expensive and quite fragile.
post war period
After the Second World War, devices for receiving FM transmitters with frequency modulation came onto the market from 1949 with the start of VHF broadcasting in Germany . Like many products in post-war Germany , these were still relatively expensive in terms of income. In 1952 z. B. a superimposition receiver (Superhet / Super) with VHF range in West Germany 380 DM (corresponds to inflation-adjusted in today's currency 967 euros). VHF reception was also possible for the existing radio receivers with inexpensive additional devices.
Components
In early analog radios, apart from the detector receiver , devices with electron tubes were also used for reception and amplification, which is why they are called tube receivers . The reception principles of these tube receivers were the audion and later the heterodyne receiver.
From the 1920s to the 1950s, stationary as well as portable devices were available exclusively as tube receivers in addition to the simpler detector receivers with detector modules or tip diodes . In 1953, an American company launched the Regency TR-1 , the first transistor radio , a pocket radio with four transistors . This innovation was by 1948 at Bell developed electronic semiconductor - component possible transistor. In Germany, the Palatinate company Akkord-Radio followed in 1957, also with a small transistor device.
Transistor radios with these new active, amplifying components had several advantages over previous devices: They were smaller, lighter, less sensitive to shocks and required comparatively little energy, so that operation with dry batteries was possible for a long time.
In addition to the stationary ones, they soon also replaced the portable devices, the portable radios, which were equipped with battery tubes and anode batteries . At times, mixed-equipped devices also appeared, in which both transistors and tubes were used.
In further development, transistors and other components such as capacitors and resistors were combined into integrated circuits from the early 1960s , which again led to size reductions, now down to pocket size. It is worth mentioning the ZN414 circuit developed by the British company Ferranti , which no longer exists , and is available from other manufacturers as TA7642 , slightly modified, to this day .
With the use of electronic components for station search and digital frequency display , for example in the Blaupunkt car radio Bamberg QTS Super Arimat (produced from 1979 to 1980), a partial digitization of analog reception technology began. The previously formative radio scales increasingly disappeared and the appearance and operation of radio sets changed fundamentally.
Circuit principles
In classic radio, the electromagnetic waves emitted by the transmitter are first converted into alternating current in a suitable antenna. This is processed in such a way that only very specific vibration frequencies - a narrow frequency range around z. B. 801 kHz, in which a certain radio program is transmitted - selected and amplified and the transmitted content - speech, sounds, music - is recovered in its original frequency position for playback via speakers . On the basis of the circuit principle used for this task, a distinction is made, among other things, between straight-ahead receiver and superimposition receiver.
Further developments
A revival in radio sales brought u. a. in Germany the VHF or FM stereo broadcast presented in August 1963 at the 23rd Great German Radio Exhibition in Berlin . In the 1970s, the simple, mostly portable transistor radios developed into stereo device combinations with cassette recorders and, ten years later, a CD player . These radio recorders were widespread in youth culture until the late 1980s. The radio service of the Automobile Driver Broadcasting Information (ARI) and the Radio Data System (RDS) were milestones in the development of analog receivers, especially car radios. The term car radio is often used as a synonym for the entire car hi-fi system, today often combined with a navigation system.
For radio amateurs as for foreign tourists were Weltempfänger popular radio equipment that are specific to a worldwide viewing of programs of short wave broadcasting are optimized.
The miniaturization led by Matchbox -large mini radios with earphones or headphones over those supplemented by a radio part Walkman devices that the Japanese company Sony produced the first small player for compact cassettes up to in mobile phones built-in radio receivers.
The radio receiving part in so-called radiograms in a mono- such as stereo , in radio recorders, mobile phones or other combined equipment is independent of device size, and on whether it as a single unit or as an integral part or built-in circuit board is produced in a combination of devices - in the technical jargon referred to as a tuner (dt. tunable receiver). In conjunction with an audio amplifier , the device's receiver or receiver.
Modulation types
Since the early days of radio broadcasting, analogue transmission and reception of radio broadcasts have been made in amplitude modulation (AM). This affects broadcasting stations that broadcast their programs on long wave (LW), medium wave (MW) and / or short wave (KW). This is often referred to in general as AM broadcasting. In addition to the predominantly monophonic broadcast, there is also AM stereo , a method for stereophony in the transmission of AM radio using quadrature amplitude modulation (QAM).
Transmitter of the FM broadcast not transmitted with AM, but with frequency modulation (FM). As a result, radio reception for local broadcasters was significantly less interference than with the previous AM radio reception on long, medium or short wave. However, VHF transmitters only allow a significantly shorter range than AM stations, which is due to the different propagation behavior of the various frequency and wave ranges . A remote reception of at least 100 kilometers, as is consistently possible in the AM areas, can not be achieved in the VHF area , apart from occasional overreaches , since the distance of the propagation is limited by the so - called quasi - optical distance ( ).
Despite the increasing expansion from the 1950s of the transmission network of the younger VHF waveband, there was no mutual suppression, but AM and VHF broadcasting followed in parallel for many decades. Starting in 1963, there was FM stereo receiver with two Hörkanälen (left and right ear) - for their transmission deviating from AM stereo, a pilot tone - multiplexing method is applied.
In the 1970s, traffic radio was introduced in Europe and North America using different methods, and in the 1980s the Radio Data System (RDS) was introduced using binary phase modulation (BPSK), a special digital phase modulation.
It should be noted that AM and FM were originally developed as types of modulation for analog transmission, but can also be used for digital transmission.
Analog shutdown
In Europe, many powerful analog long, medium and short wave transmitters have been abandoned since 1992. A complete analogue switch-off (or "switch-off") has not yet taken place.
Digital radio reception
The development of digital transmission technologies and end devices began at the end of the 20th century. Without the equipment of an additional respective digital or analogue receiver, it is not possible to receive analogue radio stations with digital radios and vice versa from digital stations with analogue receivers.
Digital transmission
For digital radio reception, such as Suitable devices are required, for example DAB , DAB + and DRM . Radio stations are also transmitted digitally via DVB-S , DVB-C and, in a few areas, via DVB-T . A special receiver (tuner or digital receiver ), often called a set-top box , is required for each of these technologies , whereby existing hi-fi systems, PC loudspeakers or television sets can be used to reproduce the sounds.
The so-called analog switch-off, i.e. switching radio stations to digital broadcasting, should force consumers to purchase new radio receivers for digital reception. In addition to the pure transmission of audio content, digital radio should become more important in new systems, for example for the transmission of traffic telematics information (e.g. TMC or TPEG ) or for the structured transmission of audio objects that allow interactive use.
However, the imminent shutdown of analog FM stations is now viewed as extremely dubious, as there are no signs of a breakthrough for digital radio in Europe - the only exception here is Great Britain with a digital quota of around 20 percent (as of 2012). Experts largely agree that analogue VHF or FM broadcasting will continue (at least) for the next ten to 15 years until digital radio (if at all) has achieved sufficient market penetration.
Digital Radio Mondiale
Today, AM radio stations also broadcast medium, long and short wave using the digital transmission method, Digital Radio Mondiale, which enables stereophonic transmission with better sound quality. Although a possible analog “switch-off” for broadcasts in AM is already being discussed in these frequency ranges, this has not yet taken place.
Software defined radio
The digitization of the previously predominantly analog radio is being systematically continued with the introduction of Software Defined Radio (SDR). Software-defined radio should, if possible, define the entire signal processing of a high-frequency transmitter or receiver using adaptable hardware via software . With exchangeable software modules , new digital transmission methods can be implemented.
SDR technology offers the possibility of testing more efficient radio transmission systems with new software modules without the existing SDR receivers becoming unusable after a software update. In the narrower sense, this is a radio telecommunications system that uses software-configurable hardware for modulation and demodulation and for upward or downward mixing of a data signal. Today, SDR receivers are offered both for amateur radio and for receiving DRM broadcasts.
Internet radio and streaming
In digital broadcasting , the audio signals are distributed as a so-called broadcast , while in live streaming for web radio, the data is usually only sent out directly addressed to the recipient after a request ( client-server model ). Like digital broadcasting, Internet radio is often referred to as digital radio .
The data transmission of the internet radio takes place terrestrially ( WLAN , WiMAX , UMTS ), as well as via copper cables , fiber optic cables and via communication satellites . The audio format is not fixed; however, common streaming formats such as MP3 or WMA are mostly used. The spread is practically the same as the spread of the Internet, which makes "broadcasting" comparatively easy for radio stations.
The radio user needs a corresponding streaming client to receive the internet radio . Such clients are readily available on the Internet, and often free of charge. For the operator of native Internet broadcasters, on the other hand, the technical effort involved in operating them is limited. Because of these factors, Internet radio could become very important as a digital radio. In 2009 there were more than 1900 internet radio stations in Germany; the average usage time was 73 minutes per day. The reception can take place via a personal computer or via special Internet radio devices. Pure internet radio devices are already on the market.
In 2006, more than 20 million people across Europe were listening to Internet radio; the forecast for 2010 was almost 32 million listeners.
Media libraries and podcasting
In addition to the radio program, internet presences and websites were created which offered the possibility of many established radio stations to listen to selected radio programs for a while as a podcast , in the form of a media library or as a subscriber . There is the possibility for interested parties and teachers to download text content for the broadcast to read . With the creation of a continuously updated web journal with an article tree that is extended and continuously updated compared to the radio, including images and links to sources, web presences were created with an additional benefit compared to a pure radio broadcast program.
See also
literature
- Heinz Lange, Heinz K. Nowisch: Receiver circuits in the radio industry. Deutscher Funk-Verlag, Berlin-Treptow, online edition. [1]
- Günter F. Abele: Historical radios. A chronicle in words and pictures. 5 vol., Füsslin, Stuttgart 1996–1999, ISBN 3-9803451-4-9 .
- Günter F. Abele: Radio Chronicle. From the post-war period to the present. Füsslin, Stuttgart 2003, ISBN 3-9803451-8-1 .
- Hans-Jürgen Krug : Radio. UTB, Stuttgart 2010, ISBN 978-3-8252-3333-4 .
- Eike Grund: Radios from the 1950s. Restoration, recommissioning and repair. egrund, Dietmannsried 2004, ISBN 3-8330-0357-X .
- Martin Gerhard Wegener: Modern radio reception technology. Franzis, Munich 1985, ISBN 3-7723-7911-7 .
- Uta C. Schmidt: From "toys" to "house friends" to "Goebbels snout". The radio as a domestic communication medium in the German Reich (1923-1945) . In: Technikgeschichte, Vol. 65 (1998), H. 4, pp. 313-327.
Web links
- Link catalog on radio at curlie.org (formerly DMOZ )
- German radio collector and radio history website
- History of modern radio sets. In: Wiener Bilder , May 10, 1925, p. 8 (online at ANNO ). (Photo report)
- Edzard Schade: Radio. In: Historical Lexicon of Switzerland .
Individual evidence
- ↑ Der deutsche Rundfunk , issue 30 of July 27, 1924, p. 1665 ff.
- ↑ Helmut Schanze : Radio, Medium and Mass. Requirements and consequences of medialization after the 1st World War . In: The idea of the radio. in the yearbook Media and History 2004. UVK Verlagsgesellschaft, Konstanz 2004, p. 18 ff.
- ^ Eva Susanne Breßler: From the experimental stage to the propaganda instrument: The history of the radio exhibition 1924 to 1939. Böhlau Verlag GmbH, Cologne / Weimar / Vienna 2009, page 73 ff. ISBN 978-3-412-20241-5 .
- ↑ Wolfgang Ruppert: Chiffren des Alltags: Explorations on the history of industrial mass culture. Jonas Verlag, Marburg 1993. Page 68 f.
- ↑ Gregory Malanowsi: The Race for Wireless: How Radio What Invented (or Discovered?). Page 105 ff., ISBN 978-1-4634-3750-3 .
- ↑ OE333 receiver, H.-T. Schmidt
- ↑ This figure was determined with the template: Inflation and relates to last January.
- ↑ B. Kainka: Medium wave receiver TA7642 . Publications by Franzis-Verlag , TA7642 ( Memento of the original dated May 6, 2014 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed May 5, 2015
- ↑ The Guardian: Nearly 30% of radio listening goes digital - but share of DAB radio slips DAB radio slipped back to 19.1% from a 19.4% , article from May 17, 2012
- ↑ BLM-WebradioMonitor 2009: Internet radio usage in Germany ( Memento from July 5, 2010 in the Internet Archive ) (PDF; 1.7 MB)
- ↑ Example for Internet radio device : “Kitchen radio plays music via WLAN” , golem.de, March 10, 2006.
- ↑ "Radio on the Internet: 20 million tune in" , golem.de, September 11, 2006.
