Talk:Radio/Archive 3

Uncited material in need of citations
I am moving the following uncited material here until it can be properly supported with inline citations of reliable, secondary sources, per WP:V, WP:NOR, WP:CS, WP:NOR, WP:IRS, WP:PSTS, et al. This diff shows where it was in the article. Nightscream (talk) 14:34, 13 August 2022 (UTC)

Moved material
...thus accelerating. In transmission, a transmitter generates an alternating current of radio frequency which is applied to an antenna. The antenna radiates the power in the current as radio waves. When the waves strike the antenna of a radio receiver, they push the electrons in the metal back and forth, inducing a tiny alternating current. The radio receiver connected to the receiving antenna detects this oscillating current and amplifies it.
 * ==Technology==

As they travel farther from the transmitting antenna, radio waves spread out so their signal strength (intensity in watts per square meter) decreases, so radio transmissions can only be received within a limited range of the transmitter, the distance depending on the transmitter power, the antenna radiation pattern, receiver sensitivity, noise level, and presence of obstructions between transmitter and receiver. An omnidirectional antenna transmits or receives radio waves in all directions, while a directional antenna or high-gain antenna transmits radio waves in a beam in a particular direction, or receives waves from only one direction.

...and in the air at very close to the speed of light. So the wavelength of a radio wave, the distance in meters between adjacent crests of the wave, is inversely proportional to its frequency, equal to the speed of light divided by the frequency.

Radio waves have the ability to pass through the atmosphere in any weather, foliage, and most building materials, and by diffraction can bend around obstructions, and unlike other electromagnetic waves, they tend to be scattered rather than absorbed by objects larger than their wavelength.

The modulation signal may be an audio signal representing sound from a microphone, a video signal representing moving images from a video camera, or a digital signal consisting of a sequence of bits representing binary data from a computer. The modulation signal is applied to a radio transmitter. In the transmitter, an electronic oscillator generates an alternating current oscillating at a radio frequency, called the carrier wave because it serves to "carry" the information through the air. The information signal is used to modulate the carrier, varying some aspect of the carrier wave, impressing the information on the carrier. Different radio systems use different modulation methods:
 * AM (amplitude modulation) – in an AM transmitter, the amplitude (strength) of the radio carrier wave is varied by the modulation signal;
 * FM (frequency modulation) – in an FM transmitter, the frequency of the radio carrier wave is varied by the modulation signal;
 * FSK (frequency-shift keying) – used in wireless digital devices to transmit digital signals, the frequency of the carrier wave is shifted periodically between two frequencies that represent the two binary digits, 0 and 1, to transmit a sequence of bits;
 * OFDM (orthogonal frequency-division multiplexing) – a family of complicated digital modulation methods very widely used in high bandwidth systems such as Wi-Fi networks, cellphones, digital television broadcasting, and digital audio broadcasting (DAB) to transmit digital data using a minimum of radio spectrum bandwidth. It has higher spectral efficiency and more resistance to fading than AM or FM.  In OFDM, multiple radio carrier waves closely spaced in frequency are transmitted within the radio channel, with each carrier modulated with bits from the incoming bitstream so multiple bits are being sent simultaneously, in parallel.  At the receiver, the carriers are demodulated and the bits are combined in the proper order into one bitstream.

Many other types of modulation are also used. In some types, a carrier wave is not transmitted but just one or both modulation sidebands.

The modulated carrier is amplified in the transmitter and applied to a transmitting antenna which radiates the energy as radio waves. The radio waves carry the information to the receiver location.

This voltage is applied to the radio receiver, which amplifies the weak radio signal so it is stronger, then demodulates it, extracting the original modulation signal from the modulated carrier wave. The modulation signal is converted by a transducer back to a human-usable form: an audio signal is converted to sound waves by a loudspeaker or earphones, a video signal is converted to images by a display, while a digital signal is applied to a computer or microprocessor, which interacts with human users.

It has a natural resonant frequency at which it oscillates. The resonant frequency of the receiver's tuned circuit is adjusted by the user to the frequency of the desired radio station; this is called "tuning". The oscillating radio signal from the desired station causes the tuned circuit to resonate, oscillate in sympathy, and it passes the signal on to the rest of the receiver. Radio signals at other frequencies are blocked by the tuned circuit and not passed on.

For any given signal-to-noise ratio, an amount of bandwidth can carry the same amount of information (data rate in bits per second) regardless of where in the radio frequency spectrum it is located, so bandwidth is a measure of information-carrying capacity. The bandwidth required by a radio transmission depends on the data rate of the information (modulation signal) being sent, and the spectral efficiency of the modulation method used; how much data it can transmit in each kilohertz of bandwidth. Different types of information signals carried by radio have different data rates. For example, a television (video) signal has a greater data rate than an audio signal. Each radio transmission occupies a portion of the total bandwidth available. Radio bandwidth is regarded as an economic good which has a monetary cost and is in increasing demand. In some parts of the radio spectrum, the right to use a frequency band or even a single radio channel is bought and sold for millions of dollars. So there is an incentive to employ technology to minimize the bandwidth used by radio services.
 * ==Bandwidth==

In recent years there has been a transition from analog to digital radio transmission technologies. Part of the reason for this is that digital modulation can often transmit more information (a greater data rate) in a given bandwidth than analog modulation, by using data compression algorithms, which reduce redundancy in the data to be sent, and more efficient modulation. Other reasons for the transition is that digital modulation has greater noise immunity than analog, digital signal processing chips have more power and flexibility than analog circuits, and a wide variety of types of information can be transmitted using the same digital modulation.

Because it is a fixed resource which is in demand by an increasing number of users, the radio spectrum has become increasingly congested in recent decades, and the need to use it more effectively is driving many additional radio innovations such as trunked radio systems, spread spectrum (ultra-wideband) transmission, frequency reuse, dynamic spectrum management, frequency pooling, and cognitive radio.

It can be seen that the bandwidth, the range of frequencies, contained in each band is not equal but increases exponentially as the frequency increases; each band contains ten times the bandwidth of the preceding band. The greater bandwidth available has motivated a continuing trend to exploit higher frequencies throughout radio's history. Interference with radio transmissions can not only have a large economic cost, it can be life-threatening (for example, in the case of interference with emergency communications or air traffic control).
 * ===ITU frequency bands===
 * ==Regulation==

Radio transmitters must be licensed by governments, under a variety of license classes depending on use, and are restricted to certain frequencies and power levels. In some classes, such as radio and television broadcasting stations, the transmitter is given a unique identifier consisting of a string of letters and numbers called a call sign, which must be used in all transmissions. The radio operator must hold a government license, such as the general radiotelephone operator license in the US, obtained by taking a test demonstrating adequate technical and legal knowledge of safe radio operation.

Exceptions to the above rules allow the unlicensed operation by the public of low power short-range transmitters in consumer products such as cell phones, cordless phones, wireless devices, walkie-talkies, citizens band radios, wireless microphones, garage door openers, and baby monitors. In the US, these fall under Part 15 of the Federal Communications Commission (FCC) regulations. Many of these devices use the ISM bands, a series of frequency bands throughout the radio spectrum reserved for unlicensed use. Although they can be operated without a license, like all radio equipment these devices generally must be type-approved before the sale.

Broadcasting is the one-way transmission of information from a transmitter to receivers belonging to a public audience. Since the radio waves become weaker with distance, a broadcasting station can only be received within a limited distance of its transmitter. Systems that broadcast from satellites can generally be received over an entire country or continent. Older terrestrial radio and television are paid for by commercial advertising or governments. In subscription systems like satellite television and satellite radio the customer pays a monthly fee. In these systems, the radio signal is encrypted and can only be decrypted by the receiver, which is controlled by the company and can be deactivated if the customer doesn't pay the bill.

Broadcasting uses several parts of the radio spectrum, depending on the type of signals transmitted and the desired target audience. Longwave and medium wave signals can give reliable coverage of areas several hundred kilometers across, but have the more limited information-carrying capacity and so work best with audio signals (speech and music), and the sound quality can be degraded by radio noise from natural and artificial sources. The shortwave bands have a greater potential range but are more subject to interference by distant stations and varying atmospheric conditions that affect reception.

In the very high frequency band, greater than 30 megahertz, the Earth's atmosphere has less of an effect on the range of signals, and line-of-sight propagation becomes the principal mode. These higher frequencies permit the great bandwidth required for television broadcasting. Since natural and artificial noise sources are less present at these frequencies, high-quality audio transmission is possible, using frequency modulation.


 * ====Audio: Radio broadcasting====

Radio broadcasting means transmission of audio (sound) to radio receivers belonging to a public audience. Analog audio is the earliest form of radio broadcast. AM broadcasting began around 1920. FM broadcasting was introduced in the late 1930s with improved fidelity. A broadcast radio receiver is called a radio. Most radios can receive both AM and FM and are called AM/FM receivers.
 * AM (amplitude modulation) – in AM, the amplitude (strength) of the radio carrier wave is varied by the audio signal. AM broadcasting, the oldest broadcasting technology, is allowed in the AM broadcast bands, between 148 and 283 kHz in the low frequency (LF) band, and between 526 and 1706 kHz in the medium frequency (MF) band. Because waves in these bands travel as ground waves following the terrain, AM radio stations can be received beyond the horizon at hundreds of miles distance, but AM has lower fidelity than FM.  Radiated power (ERP) of AM stations in the US is usually limited to a maximum of 10 kW, although a few (clear-channel stations) are allowed to transmit at 50 kW.  AM stations broadcast in monaural audio; AM stereo broadcast standards exist in most countries, but the radio industry has failed to upgrade to them due to lack of demand.
 * Shortwave broadcasting – AM broadcasting is also allowed in the shortwave bands by legacy radio stations. Since radio waves in these bands can travel intercontinental distances by reflecting off the ionosphere using skywave or "skip" propagation, shortwave is used by international stations, broadcasting to other countries.


 * FM (frequency modulation) – in FM the frequency of the radio carrier signal is varied slightly by the audio signal. FM broadcasting is permitted in the FM broadcast bands between about 65 and 108 MHz in the very high frequency (VHF) range. Radio waves in this band travel by line-of-sight so FM reception is limited by the  visual horizon to about 30-40 miles, and can be blocked by hills.  However it is less susceptible to interference from radio noise (RFI, sferics, static) and has higher fidelity; better frequency response and less audio distortion, than AM. In the US, radiated power (ERP) of FM stations varies from 6 to 100 kW.


 * ====Audio: Radio broadcasting====

DAB has the potential to provide higher quality sound than FM (although many stations do not choose to transmit at such high quality), has greater immunity to radio noise and interference, makes better use of scarce radio spectrum bandwidth and provides advanced user features such as electronic program guides. Its disadvantage is that it is incompatible with previous radios so that a new DAB receiver must be purchased. Most countries plan an eventual switchover from FM to DAB. The United States and Canada have chosen not to implement DAB.


 * A single DAB station transmits a 1,500 kHz bandwidth signal that carries from 9 to 12 channels of digital audio modulated by OFDM from which the listener can choose. Broadcasters can transmit a channel at a range of different bit rates, so different channels can have different audio quality.  In different countries DAB stations broadcast in either Band III (174–240 MHz) or L band (1.452–1.492 GHz) in the UHF range, so like FM reception is limited by the visual horizon to about 40 miles.


 * Digital Radio Mondiale (DRM) is a competing digital terrestrial radio standard developed mainly by broadcasters as a higher spectral efficiency replacement for legacy AM and FM broadcasting. Mondiale means "worldwide" in French and Italian, and DRM, developed in 2001, is currently supported by 23 countries and has been adopted by some European and Eastern broadcasters beginning in 2003. The DRM30 mode uses the AM broadcast bands below 30 MHz and is intended as a replacement for AM and shortwave broadcasting, and the DRM+ mode uses VHF frequencies centered on the FM broadcast band and is intended as a replacement for FM broadcasting.  It is incompatible with existing radio receivers and requires listeners to purchase a new DRM receiver. The modulation used is a form of OFDM called COFDM in which up to 4 carriers are transmitted in a channel formerly occupied by a single AM or FM signal, modulated by quadrature amplitude modulation (QAM).  The DRM system is designed to be as compatible as possible with existing AM and FM radio transmitters, so much of the equipment in existing radio stations will not have to be replaced.
 * Satellite radio is a subscription radio service that broadcasts CD quality digital audio direct to subscribers' receivers using a microwave downlink signal from a direct broadcast communication satellite in geostationary orbit 22,000 miles above the Earth. It is mostly intended for car radios in vehicles.  Satellite radio uses the 2.3 GHz S band in North America, in other parts of the world, it uses the 1.4 GHz L band allocated for DAB.


 * ====Video: Television broadcasting====

Television broadcasting is the transmission of moving images by radio, which consist of sequences of still images, which are displayed on a screen on a television receiver (a "television" or TV) along with a synchronized audio (sound) channel. Television (video) signals occupy a wider bandwidth than broadcast radio (audio) signals. Analog television, the original television technology, required 6 MHz, so the television frequency bands are divided into 6 MHz channels, now called "RF channels". The current television standard, introduced beginning in 2006, is a digital format called high-definition television (HDTV), which transmits pictures at higher resolution, typically 1080 pixels high by 1920 pixels wide, at a rate of 25 or 30 frames per second. Digital television (DTV) transmission systems, which replaced older analog television in a transition beginning in 2006, use image compression and high-efficiency digital modulation such as OFDM and 8VSB to transmit HDTV video within a smaller bandwidth than the old analog channels, saving scarce radio spectrum space. Therefore, each of the 6 MHz analog RF channels now carries up to 7 DTV channels – these are called "virtual channels". Digital television receivers have different behavior in the presence of poor reception or noise than analog television, called the "digital cliff" effect. Unlike analog television, in which increasingly poor reception causes the picture quality to gradually degrade, in digital television picture quality is not affected by poor reception until, at a certain point, the receiver stops working and the screen goes black.


 * Terrestrial television, over-the-air (OTA) television, or broadcast television – the oldest television technology, is the transmission of television signals from land-based television stations to television receivers (called televisions or TVs) in viewer's homes. Terrestrial television broadcasting uses the bands 41 – 88 MHz (VHF low band or Band I, carrying RF channels 1–6), 174 – 240 MHz, (VHF high band or Band III; carrying RF channels 7–13), and 470 – 614 MHz (UHF Band IV and Band V; carrying RF channels 14 and up).  The exact frequency boundaries vary in different countries.  Propagation is by line-of-sight, so reception is limited by the visual horizon to 30-40 miles.  In the US effective radiated power (ERP) of television, transmitters are limited to 35 kW in the VHF low band, 50 kW in the VHF high band, and 220 kW in UHF band; most TV stations operate below 75% of the limit.  In most areas, viewers use a simple "rabbit ears" dipole antenna on top of the TV, but viewers in fringe reception areas more than 15 miles from a station usually have to use an outdoor antenna mounted on the roof to get adequate reception.


 * Satellite television – a set-top box which receives subscription direct-broadcast satellite television, and displays it on an ordinary television. A direct broadcast satellite in geostationary orbit 22200 mi above the Earth's equator transmits many channels (up to 900) modulated on a 12.2 to 12.7 GHz Ku band microwave downlink signal to a rooftop satellite dish antenna on the subscriber's residence. The microwave signal is converted to a lower intermediate frequency at the dish and conducted into the building by a coaxial cable to a set-top box connected to the subscriber's TV, where it is demodulated and displayed. The subscriber pays a monthly fee.

Government standard frequency and time signal services operate time radio stations which continuously broadcast extremely accurate time signals produced by atomic clocks, as a reference to synchronize other clocks. Examples are BPC, DCF77, JJY, MSF, RTZ, TDF, WWV, and YVTO. One use is in radio clocks and watches, which include an automated receiver that periodically (usually weekly) receives and decodes the time signal and resets the watch's internal quartz clock to the correct time, thus allowing a small watch or desk clock to have the same accuracy as an atomic clock. Government time stations are declining in number because GPS satellites and the Internet Network Time Protocol (NTP) provide equally accurate time standards.
 * ====Time====


 * ===Two-way voice communication===

A two-way radio is an audio transceiver, a receiver and transmitter in the same device, used for bidirectional person-to-person voice communication with other users with similar radios. An older term for this mode of communication is radiotelephony. The radio link may be half-duplex, as in a walkie-talkie, using a single radio channel in which only one radio can transmit at a time, so different users take turns talking, pressing a "push to talk" button on their radio which switches off the receiver and switches on the transmitter. Or the radio link may be full duplex, a bidirectional link using two radio channels so both people can talk at the same time, as in a cell phone.

All the cell phones in a cell communicate with this antenna on separate frequency channels, assigned from a common pool of frequencies. The purpose of cellular organization is to conserve radio bandwidth by frequency reuse. Low power transmitters are used so the radio waves used in a cell do not travel far beyond the cell, allowing the same frequencies to be reused in geographically separated cells. When a user carrying a cellphone crosses from one cell to another, his phone is automatically "handed off" seamlessly to the new antenna and assigned new frequencies. Cellphones have a highly automated full duplex digital transceiver using OFDM modulation using two digital radio channels, each carrying one direction of the bidirectional conversation, as well as a control channel that handles dialing calls and "handing off" the phone to another cell tower. Older 2G, 3G, and 4G networks use frequencies in the UHF and low microwave range, between 700 MHz and 3 GHz. The cell phone transmitter adjusts its power output to use the minimum power necessary to communicate with the cell tower; 0.6 W when near the tower, up to 3 W when farther away. Cell tower channel transmitter power is 50 W. Current generation phones, called smartphones, have many functions besides making telephone calls, and therefore have several other radio transmitters and receivers that connect them with other networks: usually a Wi-Fi modem, a Bluetooth modem, and a GPS receiver.
 * 5G cellular network – next-generation cellular networks which began deployment in 2019. Their major advantage is much higher data rates than previous cellular networks, up to 10 Gbps; 100 times faster than the previous cellular technology, 4G LTE. The higher data rates are achieved partly by using higher frequency radio waves, in the higher microwave band 3–6 GHz, and millimeter wave band, around 28 and 39 GHz.  Since these frequencies have a shorter range than previous cellphone bands, the cells will be smaller than the cells in previous cellular networks which could be many miles across.  Millimeter-wave cells will only be a few blocks long, and instead of a cell base station and antenna tower, they will have many small antennas attached to utility poles and buildings.


 * Satellite phone (satphone) – a portable wireless telephone similar to a cell phone, connected to the telephone network through a radio link to an orbiting communications satellite instead of through cell towers. They are more expensive than cell phones; but their advantage is that, unlike a cell phone which is limited to areas covered by cell towers, satphones can be used over most or all of the geographical area of the Earth.  In order for the phone to communicate with a satellite using a small omnidirectional antenna, first-generation systems use satellites in low Earth orbit, about 400-700 mi above the surface.  With an orbital period of about 100 minutes, a satellite can only be in view of a phone for about 4 – 15 minutes, so the call is "handed off" to another satellite when one passes beyond the local horizon. Therefore, large numbers of satellites, about 40 to 70, are required to ensure that at least one satellite is in view continuously from each point on Earth.  Other satphone systems use satellites in geostationary orbit in which only a few satellites are needed, but these cannot be used at high latitudes because of terrestrial interference.
 * Cordless phone – a landline telephone in which the handset is portable and communicates with the rest of the phone by a short-range full duplex radio link, instead of being attached by a cord. Both the handset and the base station have low-power FM radio transceivers operating in the UHF band that handles the short-range bidirectional radio link.

These systems have a fairly limited range, usually 3 to 20 miles depending on terrain. Repeaters installed on tall buildings, hills, or mountain peaks are often used to increase the range when it is desired to cover a larger area than line-of-sight. Examples of land mobile systems are CB, FRS, GMRS, and MURS. Modern digital systems, called trunked radio systems, have a digital channel management system using a control channel that automatically assigns frequency channels to user groups.
 * Walkie-talkie – a battery-powered portable handheld half-duplex two-way radio, used in land mobile radio systems. * Airband – Half-duplex radio system used by aircraft pilots to talk to other aircraft and ground-based air traffic controllers. This vital system is the main communication channel for air traffic control.  For most communication in overland flights in air corridors a VHF-AM system using channels between 108 and 137 MHz in the VHF band are used.  This system has a typical transmission range of 200 miles for aircraft flying at cruising altitude. For flights in more remote areas, such as transoceanic airline flights, aircraft use the HF band or channels on the Inmarsat or Iridium satphone satellites.  Military aircraft also use a dedicated UHF-AM band from 225.0 to 399.95 MHz.


 * Marine radio – medium-range transceivers on ships, used for ship-to-ship, ship-to-air, and ship-to-shore communication with harbormasters They use FM channels between 156 and 174 MHz in the VHF band with up to 25 watts power, giving them a range of about 60 miles. Some channels are half-duplex and some are full-duplex, to be compatible with the telephone network, to allow users to make telephone calls through a marine operator.
 * Amateur radio – long-range half-duplex two-way radio used by hobbyists for non-commercial purposes: recreational radio contacts with other amateurs, volunteer emergency communication during disasters, contests, and experimentation. Radio amateurs must hold an amateur radio license and are given a unique callsign that must be used as an identifier in transmissions. Amateur radio is restricted to small frequency bands, the amateur radio bands, spaced throughout the radio spectrum from 136 kHz to 2.4 GHz.  Within these bands, amateurs are allowed the freedom to transmit on any frequency with a wide variety of modulation methods.  In addition to radiotelephony, amateurs are the only radio operators still using Morse code radiotelegraphy.

One way, unidirectional radio transmission is called simplex.
 * ===One-way voice communication===
 * Baby monitor – a crib-side appliance for parents of infants that transmits the baby's sounds to a receiver carried by the parent, so they can monitor the baby while they are in other parts of the house. These transmit in FM on 49.300, 49.830, 49.845, 49.860, or 49.875 MHz with low power.  Many baby monitors have duplex channels so the parent can talk to the baby, and video cameras to show a picture of the baby, this is called a baby cam.
 * Wireless microphone – a battery-powered microphone with a short-range transmitter that is handheld or worn on a person's body which transmits its sound by radio to a nearby receiver unit connected to a sound system. Wireless microphones are used by public speakers, performers, and television personalities so they can move freely without trailing a microphone cord.  Analog models transmit in FM on unused portions of the television broadcast frequencies in the VHF and UHF bands.  Some models transmit on two frequency channels for diversity reception to prevent nulls from interrupting transmission as the performer moves around.  Some models use digital modulation to prevent unauthorized reception by scanner radio receivers; these operate in the 900 MHz, 2.4 GHz or 6 GHz ISM bands.


 * ===Data communication===


 * Wireless networking – automated radio links which transmit digital data between computers and other wireless devices using radio waves, linking the devices together transparently in a computer network. Computer networks can transmit any form of data: in addition to email and web pages, they also carry phone calls (VoIP), audio, and video content (called streaming media).  Security is more of an issue for wireless networks than for wired networks since anyone nearby with a wireless modem can access the signal and attempt to log in. The radio signals of wireless networks are encrypted using WPA.Wireless network.jpg and typical home wireless router (right) connecting it to the Internet]]
 * Wireless LAN (wireless local area network or Wi-Fi) – based on the IEEE 802.11 standards, these are the most widely used computer networks, used to implement local area networks without cables, linking computers, laptops, cell phones, video game consoles, smart TVs and printers in a home or office together, and to a wireless router connecting them to the Internet with a wire or cable connection. Wireless routers in public places like libraries, hotels and coffee shops create wireless access points (hotspots) to allow the public to access the Internet with portable devices like smartphones, tablets or laptops.  Each device exchanges data using a wireless modem (wireless network interface controller), an automated microwave transmitter and receiver with an omnidirectional antenna that works in the background, exchanging data packets with the router.  Wi-Fi uses channels in the 2.4 GHz and 5 GHz ISM bands with OFDM (orthogonal frequency-division multiplexing) modulation to transmit data at high rates.  The transmitters in Wi-Fi modems are limited to a radiated power of 200 mW to 1 watt, depending on country. They have a maximum indoor range of about 150 ft on 2.4 GHz and 50 ft on 5 GHz.USI router.jpg
 * Wireless WAN (wireless wide area network, WWAN) – a variety of technologies that provide wireless internet access over a wider area than Wi-Fi networks do – from an office building to a campus to a neighborhood, or to an entire city. The most common technologies used are: cellular modems, that exchange computer data by radio with cell towers; satellite internet access; and lower frequencies in the UHF band, which have a longer range than Wi-Fi frequencies.  Since WWAN networks are much more expensive and complicated to administer than Wi-Fi networks, their use so far has generally been limited to private networks operated by large corporations.
 * Bluetooth – a very short-range wireless interface on a portable wireless device used as a substitute for a wire or cable connection, mainly to exchange files between portable devices and connect cellphones and music players with wireless headphones. In the most widely used mode, transmission power is limited to 1 milliwatt, giving it a very short range of up to 10 m (30 feet).  The system uses frequency-hopping spread spectrum transmission, in which successive data packets are transmitted in a pseudorandom order on one of 79 1 MHz Bluetooth channels between 2.4 and 2.83 GHz in the ISM band.  This allows Bluetooth networks to operate in the presence of noise, other wireless devices and other Bluetooth networks using the same frequencies, since the chance of another device attempting to transmit on the same frequency at the same time as the Bluetooth modem is low.  In the case of such a "collision", the Bluetooth modem just retransmits the data packet on another frequency.
 * Packet radio – a long-distance peer-to-peer wireless ad-hoc network in which data packets are exchanged between computer-controlled radio modems (transmitter/receivers) called nodes, which may be separated by miles, and maybe mobile. Each node only communicates with neighboring nodes, so packets of data are passed from node to node until they reach their destination.  Uses the X.25 network protocol. Packet radio systems are used to a limited degree by commercial telecommunications companies and by the amateur radio community.
 * Text messaging (texting) – this is a service on cell phones, allowing a user to type a short alphanumeric message and send it to another phone number, and the text is displayed on the recipient's phone screen. It is based on the Short Message Service (SMS) which transmits using spare bandwidth on the control radio channel used by cell phones to handle background functions like dialing and cell handoffs. Due to technical limitations of the channel, text messages are limited to 160 alphanumeric characters.


 * Microwave relay – a long-distance high bandwidth point-to-point digital data transmission link consisting of a microwave transmitter connected to a dish antenna that transmits a beam of microwaves to another dish antenna and receiver. Since the antennas must be in line-of-sight, distances are limited by the visual horizon to 30-40 miles. Microwave links are used for private business data, wide area computer networks (WANs), and by telephone companies to transmit long- distance phone calls and television signals between cities.
 * Telemetry – automated one-way (simplex) transmission of measurements and operation data from a remote process or device to a receiver for monitoring. Telemetry is used for in-flight monitoring of missiles, drones, satellites, and weather balloon radiosondes, sending scientific data back to Earth from interplanetary spacecraft, communicating with electronic biomedical sensors implanted in the human body, and well logging. Multiple channels of data are often transmitted using frequency-division multiplexing or time-division multiplexing. Telemetry is starting to be used in consumer applications such as:
 * Automated meter reading – electric power meters, water meters, and gas meters that, when triggered by an interrogation signal, transmit their readings by radio to a utility reader vehicle at the curb, to eliminate the need for an employee to go on the customer's property to manually read the meter.
 * Electronic toll collection – on toll roads, an alternative to manual collection of tolls at a toll booth, in which a transponder in a vehicle, when triggered by a roadside transmitter, transmits a signal to a roadside receiver to register the vehicle's use of the road, enabling the owner to be billed for the toll.


 * Radio Frequency Identification (RFID) – identification tags containing a tiny radio transponder (receiver and transmitter) which are attached to merchandise. When it receives an interrogation pulse of radio waves from a nearby reader unit, the tag transmits back an ID number, which can be used to inventory goods.  Passive tags, the most common type, have a chip powered by the radio energy received from the reader, rectified by a diode, and can be as small as a grain of rice.  They are incorporated in products, clothes, railroad cars, library books, airline baggage tags and are implanted under the skin in pets and livestock (microchip implant) and even people. Privacy concerns have been addressed with tags that use encrypted signals and authenticate the reader before responding.  Passive tags use 125–134 kHz, 13, 900 MHz and 2.4 and 5 GHz ISM bands and have a short range.  Active tags, powered by a battery, are larger but can transmit a stronger signal, giving them a range of hundreds of meters.
 * Submarine communication – When submerged, submarines are cut off from all ordinary radio communication with their military command authorities by the conductive seawater. However radio waves of low enough frequencies, in the VLF (30 to 3 kHz) and ELF (below 3 kHz) bands are able to penetrate seawater.  Navies operate large shore transmitting stations with power output in the megawatt range to transmit encrypted messages to their submarines in the world's oceans.  Due to the small bandwidth, these systems cannot transmit voice, only text messages at a slow data rate. The communication channel is one-way, since the long antennas needed to transmit VLF or ELF waves cannot fit on a submarine.  VLF transmitters use miles long wire antennas like umbrella antennas.  A few nations use ELF transmitters operating around 80 Hz, which can communicate with submarines at lower depths.  These use even larger antennas called ground dipoles, consisting of two ground (Earth) connections 23-60 km apart, linked by overhead transmission lines to a power plant transmitter.

This is radio communication between a spacecraft and an Earth-based ground station, or another spacecraft. Communication with spacecraft involves the longest transmission distances of any radio links, up to billions of kilometers for interplanetary spacecraft. In order to receive the weak signals from distant spacecraft, satellite ground stations use large parabolic "dish" antennas up to 25 m in diameter and extremely sensitive receivers. High frequencies in the microwave band are used, since microwaves pass through the ionosphere without refraction, and at microwave frequencies the high-gain antennas needed to focus the radio energy into a narrow beam pointed at the receiver are small and take up a minimum of space in a satellite. Portions of the UHF, L, C, S, ku and ka band are allocated for space communication. A radio link that transmits data from the Earth's surface to a spacecraft is called an uplink, while a link that transmits data from the spacecraft to the ground is called a downlink.

Most are in geostationary orbit 22200 mi above the equator, so that the satellite appears stationary at the same point in the sky, so the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track it. In a satellite ground station a microwave transmitter and large satellite dish antenna transmit a microwave uplink beam to the satellite. The uplink signal carries many channels of telecommunications traffic, such as long-distance telephone calls, television programs, and internet signals, using a technique called frequency-division multiplexing (FDM). On the satellite, a transponder receives the signal, translates it to a different downlink frequency to avoid interfering with the uplink signal, and retransmits it down to another ground station, which may be widely separated from the first. There the downlink signal is demodulated and the telecommunications traffic it carries is sent to its local destinations through landlines. Communication satellites typically have several dozen transponders on different frequencies, which are leased by different users.
 * Direct broadcast satellite – a geostationary communication satellite that transmits retail programming directly to receivers in subscriber's homes and vehicles on Earth, in satellite radio and TV systems. It uses a higher transmitter power than other communication satellites, to allow the signal to be received by consumers with a small unobtrusive antenna.  For example, satellite television uses downlink frequencies from 12.2 to 12.7 GHz in the ku band transmitted at 100 to 250 watts, which can be received by relatively small 43-80 cm satellite dishes mounted on the outside of buildings.


 * ===Radar===

Radar is a radiolocation method used to locate and track aircraft, spacecraft, missiles, ships, vehicles, and also to map weather patterns and terrain. A radar set consists of a transmitter and receiver. The transmitter emits a narrow beam of radio waves which is swept around the surrounding space. When the beam strikes a target object, radio waves are reflected back to the receiver. The direction of the beam reveals the object's location. Since radio waves travel at a constant speed close to the speed of light, by measuring the brief time delay between the outgoing pulse and the received "echo", the range to the target can be calculated. The targets are often displayed graphically on a map display called a radar screen. Doppler radar can measure a moving object's velocity, by measuring the change in frequency of the return radio waves due to the Doppler effect.

Radar sets mainly use high frequencies in the microwave bands, because these frequencies create strong reflections from objects the size of vehicles and can be focused into narrow beams with compact antennas. Parabolic (dish) antennas are widely used. In most radars the transmitting antenna also serves as the receiving antenna; this is called a monostatic radar. A radar which uses separate transmitting and receiving antennas is called a bistatic radar.


 * Airport surveillance radar – In aviation, radar is the main tool of air traffic control. A rotating dish antenna sweeps a vertical fan-shaped beam of microwaves around the airspace and the radar set shows the location of aircraft as "blips" of light on a display called a radar screen.  Airport radar operates at 2.7 – 2.9 GHz in the microwave S band.  In large airports the radar image is displayed on multiple screens in an operations room called the TRACON (Terminal Radar Approach Control), where air traffic controllers direct the aircraft by radio to maintain safe aircraft separation.
 * Secondary surveillance radar – Aircraft carry radar transponders, transceivers which when triggered by the incoming radar signal transmit a return microwave signal. This causes the aircraft to show up more strongly on the radar screen.  The radar which triggers the transponder and receives the return beam, usually mounted on top of the primary radar dish, is called the secondary surveillance radar.  Since radar cannot measure an aircraft's altitude with any accuracy, the transponder also transmits back the aircraft's altitude measured by its altimeter, and an ID number identifying the aircraft, which is displayed on the radar screen.
 * Electronic countermeasures (ECM) – Military defensive electronic systems designed to degrade enemy radar effectiveness, or deceive it with false information, to prevent enemies from locating local forces. It often consists of powerful microwave transmitters that can mimic enemy radar signals to create false target indications on the enemy radar screens.
 * Radar altimeter – a specialized radar on an aircraft that measures the altitude of the aircraft above terrain by bouncing a radio beam off the ground surface and measuring the time for the echo to return.


 * Marine radar – an X band radar on ships used to detect nearby ships and obstructions like bridges. A rotating antenna sweeps a vertical fan-shaped beam of microwaves around the water surface surrounding the craft out to the horizon.
 * Weather radar – A Doppler radar which maps weather systems and measures wind speeds by reflection of microwaves from raindrops.
 * Phased-array radar – a radar set that uses a phased array, a computer-controlled antenna that can steer the radar beam quickly to point in different directions without moving the antenna. Phased-array radars were developed by the military to track fast-moving missiles and aircraft.  They are widely used in military equipment and are now spreading to civilian applications.
 * Synthetic aperture radar (SAR) – a specialized airborne radar set that produces a high-resolution map of ground terrain. The radar is mounted on an aircraft or spacecraft and the radar antenna radiates a beam of radio waves sideways at right angles to the direction of motion, toward the ground.  In processing the return radar signal, the motion of the vehicle is used to simulate a large antenna, giving the radar a higher resolution.
 * Ground-penetrating radar – a specialized radar instrument that is rolled along the ground surface in a cart and transmits a beam of radio waves into the ground, producing an image of subsurface objects. Frequencies from 100 MHz to a few GHz are used.  Since radio waves cannot penetrate very far into earth, the depth of GPR is limited to about 50 feet.
 * Collision avoidance system – a short range radar or LIDAR system on an automobile or vehicle that detects if the vehicle is about to collide with an object and applies the brakes to prevent the collision.
 * Radar fuze – a detonator for an aerial bomb which uses a radar altimeter to measure the height of the bomb above the ground as it falls and detonates it at a certain altitude.
 * Radar speed gun – A handheld Doppler radar used by traffic police to measure the speed of vehicles to determine if they are obeying the local speed limit. When the officer points the gun at a vehicle and presses a trigger, its speed appears on a numeric display. Speed guns use the X band or Ku band.


 * ===Radiolocation===

Radiolocation is a generic term covering a variety of techniques that use radio waves to find the location of objects, or for navigation
 * Global Navigation Satellite System (GNSS) or satnav system – A system of satellites which allows geographical location on Earth (latitude, longitude, and altitude/elevation) to be determined to high precision (within a few metres) by small portable navigation instruments, by timing the arrival of radio signals from the satellites. These are the most widely used navigation systems today.  The main satellite navigation systems are the US Global Positioning System (GPS), Russia's GLONASS, China's BeiDou Navigation Satellite System (BDS) and the European Union's Galileo.
 * Global Positioning System(GPS) – The most widely used satellite navigation system, maintained by the US Air Force, which uses a constellation of 31 satellites in low Earth orbit. The orbits of the satellites are distributed so at any time at least four satellites are above the horizon over each point on Earth.  Each satellite has an onboard atomic clock and transmits a continuous radio signal containing a precise time signal as well as its current position. Two frequencies are used, 1.2276 and 1.57542 GHz. Since the velocity of radio waves is virtually constant, the delay of the radio signal from a satellite is proportional to the distance of the receiver from the satellite.  By receiving the signals from at least four satellites a GPS receiver can calculate its position on Earth by comparing the arrival time of the radio signals.  Since each satellite's position is known precisely at any given time, from the delay the position of the receiver can be calculated by a microprocessor in the receiver. The position can be displayed as latitude and longitude, or as a marker on an electronic map.  GPS receivers are incorporated in almost all cellphones and in vehicles such as automobiles, aircraft, and ships, and are used to guide drones, missiles, cruise missiles, and even artillery shells to their target, and handheld GPS receivers are produced for hikers and the military.
 * Radio beacon – a fixed location terrestrial radio transmitter which transmits a continuous radio signal used by aircraft and ships for navigation. The locations of beacons are plotted on navigational maps used by aircraft and ships.
 * Very High-Frequency Omnidirectional Range (VOR) – a worldwide aircraft radio navigation system consisting of fixed ground radio beacons transmitting between 108.00 and 117.95 MHz in the VHF band. An automated navigational instrument on the aircraft displays a bearing to a nearby VOR transmitter. A VOR beacon transmits two signals simultaneously on different frequencies.  A directional antenna transmits a beam of radio waves that rotates like a lighthouse at a fixed rate, 30 times per second. When the directional beam is facing north, and omnidirectional antenna transmits a pulse. By measuring the difference in phase of these two signals, an aircraft can determine its bearing (or "radial") from the station accurately. By taking a bearing on two VOR beacons an aircraft can determine its position (called a "fix") to an accuracy of about 90 m.  Most VOR beacons also have a distance measuring capability, called distance measuring equipment (DME); these are called VOR/DME's.  The aircraft transmits a radio signal to the VOR/DME beacon and a transponder transmits a return signal.  From the propagation delay between the transmitted and received signal the aircraft can calculate its distance from the beacon.  This allows an aircraft to determine its location "fix" from only one VOR beacon.  Since line-of-sight VHF frequencies are used VOR beacons have a range of about 200 miles for aircraft at cruising altitude.  TACAN is a similar military radio beacon system which transmits in 962–1213 MHz, and a combined VOR and TACAN beacon is called a VORTAC. In 2000 there were about 3000 VOR beacons worldwide, but this number is declining as aviation switches to the RNAV system that relies on Global Positioning System satellite navigation.
 * Non-directional beacon (NDB) – Legacy fixed radio beacons used before the VOR system that transmit a simple signal in all directions for aircraft or ships to use for radio direction finding. Aircraft use automatic direction finder (ADF) receivers which use a directional antenna to determine the bearing to the beacon.  By taking bearings on two beacons they can determine their position.  NDBs use frequencies between 190 and 1750 kHz in the LF and MF bands which propagate beyond the horizon as ground waves or skywaves much farther than VOR beacons.  They transmit a callsign consisting of one to 3 Morse code letters as an identifier.


 * Emergency locator beacon – a portable battery powered radio transmitter used in emergencies to locate airplanes, vessels, and persons in distress and in need of immediate rescue. Various types of emergency locator beacons are carried by aircraft, ships, vehicles, hikers and cross-country skiers.  In the event of an emergency, such as the aircraft crashing, the ship sinking, or a hiker becoming lost, the transmitter is deployed and begins to transmit a continuous radio signal, which is used by search and rescue teams to quickly find the emergency and render aid.  The latest generation Emergency Position Indicating Rescue Beacons (EPIRBs) contain a GPS receiver, and broadcast to rescue teams their exact location within 20 meters.
 * Cospas-Sarsat – an international humanitarian consortium of governmental and private agencies which acts as a dispatcher for search and rescue operations. It operates a network of about 47 satellites carrying radio receivers, which detect distress signals from emergency locator beacons anywhere on Earth transmitting on the international Cospas distress frequency of 406 MHz.  The satellites calculate the geographic location of the beacon within 2 km by measuring the Doppler frequency shift of the radio waves due to the relative motion of the transmitter and the satellite, and quickly transmit the information to the appropriate local first responder organizations, which perform the search and rescue.
 * Radio direction finding (RDF) – this is a general technique, used since the early 1900s, of using specialized radio receivers with directional antennas (RDF receivers) to determine the exact bearing of a radio signal, to determine the location of the transmitter. The location of a terrestrial transmitter can be determined by simple triangulation from bearings taken by two RDF stations separated geographically, as the point where the two bearing lines cross, this is called a "fix".  Military forces use RDF to locate enemy forces by their tactical radio transmissions, counterintelligence services use it to locate clandestine transmitters used by espionage agents, and governments use it to locate unlicensed transmitters or interference sources.  Older RDF receivers used rotatable loop antennas, the antenna is rotated until the radio signal strength is weakest, indicating the transmitter is in one of the antenna's two nulls.  The nulls are used since they are sharper than the antenna's lobes (maxima).  More modern receivers use phased array antennas which have a much greater angular resolution.
 * Animal migration tracking – a widely used technique in wildlife biology, conservation biology, and wildlife management in which small battery-powered radio transmitters are attached to wild animals so their movements can be tracked with a directional RDF receiver. Sometimes the transmitter is implanted in the animal. The VHF band is typically used since antennas in this band are fairly compact.  The receiver has a directional antenna (typically a small Yagi) which is rotated until the received signal is strongest; at this point the antenna is pointing in the direction of the animal.  Sophisticated systems used in recent years use satellites to track the animal, or geolocation tags with GPS receivers which record and transmit a log of the animal's location.


 * ===Remote control===

Radio remote control is the use of electronic control signals sent by radio waves from a transmitter to control the actions of a device at a remote location. Remote control systems may also include telemetry channels in the other direction, used to transmit real-time information of the state of the device back to the control station. Unmanned spacecraft are an example of remote controlled machines, controlled by commands transmitted by satellite ground stations. Most handheld remote controls used to control consumer electronics products like televisions or DVD players actually operate by infrared light rather than radio waves, so are not examples of radio remote control. A security concern with remote control systems is spoofing, in which an unauthorized person transmits an imitation of the control signal to take control of the device. Examples of radio remote control:
 * Unmanned aerial vehicle (UAV, drone) – A drone is an aircraft without an onboard pilot, flown by remote control by a pilot in another location, usually in a piloting station on the ground. They are used by the military for reconnaissance and ground attack, and more recently by the civilian world for news reporting and aerial photography.  The pilot uses aircraft controls like a joystick or steering wheel, which create control signals which are transmitted to the drone by radio to control the flight surfaces and engine.  A telemetry system transmits back a video image from a camera in the drone to allow the pilot to see where the aircraft is going, and data from a GPS receiver giving the real-time position of the aircraft.  UAVs have sophisticated onboard automatic pilot systems that maintain stable flight and only require manual control to change directions.
 * Keyless entry system – a short-range handheld battery powered key fob transmitter, included with most modern cars, which can lock and unlock the doors of a vehicle from outside, eliminating the need to use a key. When a button is pressed, the transmitter sends a coded radio signal to a receiver in the vehicle, operating the locks.  The fob must be close to the vehicle, typically within 5 to 20 meters.  North America and Japan use a frequency of 315 MHz, while Europe uses 433.92 and 868 MHz.  Some models can also remotely start the engine, to warm up the car.  A security concern with all keyless entry systems is a replay attack, in which a thief uses a special receiver ("code grabber") to record the radio signal during opening, which can later be replayed to open the door.  To prevent this, keyless systems use a rolling code system in which a pseudorandom number generator in the remote control generates a different random key each time it is used.  To prevent thieves from simulating the pseudorandom generator to calculate the next key, the radio signal is also encrypted.
 * Garage door opener – a short-range handheld transmitter which can open or close a building's electrically operated garage door from outside, so the owner can open the door when he drives up in his car, and close it after he leaves. When a button is pressed the control transmits a coded FSK radio signal to a receiver in the opener, raising or lowering the door.  Modern openers use 310, 315 or 390 MHz.  To prevent a thief using a replay attack, modern openers use a rolling code system.


 * Radio-controlled models – a popular hobby is playing with radio-controlled model boats, cars, airplanes, and helicopters (quadcopters) which are controlled by radio signals from a handheld console with a joystick. Most recent transmitters use the 2.4 GHz ISM band with multiple control channels modulated with PWM, PCM or FSK.
 * Wireless doorbell – A residential doorbell that uses wireless technology to eliminate the need to run wires through the building walls. It consists of a doorbell button beside the door containing a small battery powered transmitter.  When the doorbell is pressed it sends a signal to a receiver inside the house with a speaker that sounds chimes to indicate someone is at the door.  They usually use the 2.4 GHz ISM band.  The frequency channel used can usually be changed by the owner in case another nearby doorbell is using the same channel.

During wartime, militaries use jamming to interfere with enemies' tactical radio communication. Since radio waves can pass beyond national borders, some totalitarian countries which practice censorship use jamming to prevent their citizens from listening to broadcasts from radio stations in other countries. Jamming is usually accomplished by a powerful transmitter which generates noise on the same frequency as the target transmitter.
 * ===Jamming===


 * ===Scientific research===
 * Radio astronomy is the scientific study of radio waves emitted by astronomical objects. Radio astronomers use radio telescopes, large radio antennas and receivers, to receive and study the radio waves from astronomical radio sources.  Since astronomical radio sources are so far away, the radio waves from them are extremely weak, requiring extremely sensitive receivers, and radio telescopes are the most sensitive radio receivers in existence. They use large parabolic (dish) antennas up to 500 meters in diameter to collect enough radio wave energy to study.  The RF front end electronics of the receiver is often cooled by liquid nitrogen to reduce thermal noise.  Multiple antennas are often linked together in arrays which function as a single antenna, to increase collecting power.  In Very Long Baseline Interferometry (VLBI) radio telescopes on different continents are linked, which can achieve the resolution of an antenna thousands of miles in diameter.
 * Remote sensing – in radio, remote sensing is the reception of electromagnetic waves radiated by natural objects or the atmosphere for scientific research. All warm objects emit microwaves and the spectrum emitted can be used to determine temperature. Microwave radiometers are used in meteorology and earth sciences to determine temperature of the atmosphere and earth surface, as well as chemical reactions in the atmosphere.

However, this invention would not be widely adopted.
 * ==Etymology==

Following Heinrich Hertz's discovery of the existence of radio waves in 1886, a variety of terms were initially used for this radiation, including "Hertzian waves", "electric waves", and "ether waves". The first practical radio communications systems, developed by Guglielmo Marconi in 1894–5, transmitted telegraph signals by radio waves, so radio communication was first called "wireless telegraphy". Up until about 1910 the term "wireless telegraphy" also included a variety of other experimental systems for transmitting telegraph signals without wires, including electrostatic induction, electromagnetic induction and aquatic and earth conduction, so there was a need for a more precise term referring exclusively to electromagnetic radiation.

The French text of both the 1903 and 1906 Berlin Radiotelegraphic Conventions includes the phrases "radiotélégraphique" and "radiotélégrammes".

This practice was universally adopted, and the word "radio" introduced internationally, by the 1906 Berlin Radiotelegraphic Convention, which included a Service Regulation specifying that "Radiotelegrams shall show in the preamble that the service is 'Radio'".

British Commonwealth countries continued to commonly use the term "wireless" until the mid-20th century, though the magazine of the British Broadcasting Corporation in the UK has been called Radio Times since its founding in the early 1920s.

The term "wireless" eventually gained renewed popularity as a more general term for devices communicating using electromagnetic radiation, either radio waves or light, due to the rapid growth of short-range computer networking, e.g., wireless local area networks Wi-Fi, and Bluetooth, as well as cell phones, to distinguish these uses from traditional "radio" communication, such as broadcasting.

Discussion

 * I think this was unwise. All this stuff is brick standard and shouldn't be controversial. Just because someone has sprinkled "cn" tags throughout doesn't mean the material isn't accurate.  It's tiresome in the extreme to footnote every single sentence, when any standard reference works on the subject will give pretty much the same uncontroversial facts. --Wtshymanski (talk) 22:13, 14 August 2022 (UTC)
 * I am opposed to this process for dealing with uncontroversial uncited material and it it looks like we have two other experienced editors similarly opposed which, as I see it, makes a consensus. I've reverted your deletion of material from the article. ~Kvng (talk) 14:35, 18 August 2022 (UTC)

I agree that long sections of the article shouldn't be totally uncited, however Wtshymanski is correct that this stuff is uncontroversial standard basics that I think he's done a good job of summarizing. Any decent textbook will adequately cover these basics: Any of these could be cited, either as general references or specific inline citations. - LuckyLouie (talk) 13:58, 15 August 2022 (UTC)
 * Basic Radio Principles and Technology - Elsevier Science
 * The Electronics of Radio - Cambridge University Press
 * Radio Systems Engineering - Cambridge University Press
 * Radio-Electronic Transmission Fundamentals - SciTech Publishing
 * Analog Electronics, Analog Circuitry Explained - Elsevier Science


 * It doesn't matter if it uncontroversial. Inline citations need to accompany the material. Nightscream (talk) 16:39, 15 August 2022 (UTC)
 * I've found at least one instance of a tag indicating a citation was needed for material that was explicitly cited . You might want to check the rest of your tags. - LuckyLouie (talk) 17:56, 15 August 2022 (UTC)


 * Nobody's perfect, but one mistake does not justify violating WP:V, et al. by restoring entire swaths of uncited material, and as a veteran editor with over 24,000 edits under your belt, you should know better. Do it again, and I'll contact an admin about your policy violations. Please do not make that necessary. If you want to improve the article, then add citations to the material in question before restoring it. For my part, I apologize if I incorrectly moved a cited passage here from the article. Nightscream (talk) 14:44, 18 August 2022 (UTC)
 * Nightscream has reverted and I won't start or continue an edit war. Here's some previous discussion of Nightscream's approach. If we don't have a consensus that this is the right approach, I encourage someone else (Wtshymanski, LuckyLouie, Johnuniq) to restore the deleted material and we can deal with the identified issues in place. ~Kvng (talk) 14:54, 18 August 2022 (UTC)
 * I haven't yet reverted anything in the article, I think Nightscream confused me with 86.181.0.154 or perhaps KVng. Yes, we all believe in WP:V as a core policy. But my personal view is that articles lacking inline citations that have been reviewed as generally accurate by editors familiar with the topic are best served with unreferenced section templates rather than inline tags for each sentence. I've listed a number of general references above. These can be applied as WP:GENREF until someone undertakes the laborious job of vetting each one as appropriate to a particular section of text. - LuckyLouie (talk) 15:32, 18 August 2022 (UTC)


 * User:86.181.0.154 appears to be another and separate editor who is opposed to Nightscream's process. There definitely is a consensus against this and @LuckyLouie has here proposed an alternative that I support. ~Kvng (talk) 16:21, 18 August 2022 (UTC)


 * There is no "consensus" on this. Two or three people violating WP:V/WP:NOR who are participating or are mentioned in a talk page discussion that hasn't been opened to the wider editing community is not a consensus. But if you want me to invite a larger numbe of editors and admins to this discussion to see if they agree with you, or if they'll tell you as I have that you are violating policy, then by all means, let me know.


 * "Reviewed as generally accurate by editors familiar with the topic" is simply one more subjective standard offered by those who try to rationalize ignoring WP:V, and like all the others I've heard, it is both vague, and stands in contrast with core Wikipedia policies that make it clear that editors' personal knowledge — which precisely what you are describing with this phrase — is not a valid basis for inclusion. Which editors are these? Who has "reviewed"? Where? When? Can you link me to these "reviews"? The only type of "review" I'm familiar with on Wikipedia is when an article is nominated for FA or GA, and in those cases, citations are always a fundamental criterion of that process. Inclusion of material on Wikipedia is based on sources, and not what editors' assert, which is original research, and is strictly prohibited. Do you dispute this? Yes or no? Please let me know.


 * Unreferenced tags are an appropriate way to alert editors that material needs citations. But this does not address what to do when material has remained uncited for a persistent length of time. Nightscream (talk) 17:35, 18 August 2022 (UTC)
 * I gather your position is that it doesn't matter how the editors of this page want to work on improving it; What matters is that it be done according to policy and that's the way you're doing it and the rest of us are violating policy.
 * I will just remind you that, creation of policy and interpretation of it is done through consensus. Consensus is more important than policy. To impose your interpretation of policy aggressively like this by tagging then removing uncontroversial content is just disruptive. ~Kvng (talk) 18:49, 18 August 2022 (UTC)
 * Nightscream, I used the word "review" in an informal sense to refer to the efforts of the article's major contributors like User:Chetvorno and User:Wtshymanski and I also prefaced my suggestions as "my personal view" and not as policy -- but I think you know that. So I'll just back off and let this play out. - LuckyLouie (talk) 19:16, 18 August 2022 (UTC)
 * Main offender here. I wrote most of the article, and didn't include sources.  I'll work on sourcing it, but it's going to be a while. --ChetvornoTALK 00:18, 19 August 2022 (UTC)

Kvng: "Consensus is more important than policy." No, consensus and policy are not mututally exclusive. Rather, Wikipedia's policies and guidelines are intended to reflect the consensus of the community. We know this because it explicitly says this here. That is not "my position" nor an "interpretation" of it. It's the explicitly stated position of the editing community here. By contrast, where is it indicated that one is "more important than" the other? For that matter, how do you personallly know what "consensus" is, if not by citation of policy? What roles do you think the site's policies and guidelines serve, if not to govern editing habits? Do you believe that a handful of editors who simply don't feel like adhering to policy can ignore it by getting together and saying "consensus" when an editor who seeks to uphold policy confronts them? Is that what you believe? If you can answer these questions, please do so. Tell me where or how you arrived at the conclusion that consensus is more important than policy. Is the above-liked passage that says that one reflects the other wrong? Or are both statements not incompatible? I want to know your thoughts on this.

Kvng: "I used the word "review" in an informal sense to refer to the efforts of the article's major contributors like User:Chetvorno and User:Wtshymanski..." It doesn't matter. Inclusion of material not determined by "reviewed as generally accurate by editors familiar with the topic," because that's called original research, and is strictly prohibited. You say that that this was a personal viewpoint of yours and not policy. I agree. And that's why it's an irrelevant standard here. We do not include material just because major contributors reviewed the material as accurate, because the standard for inclusion on Wikipedia is not accuracy. It's verifiability. This argument is even more questionable when one of those contributors you cite, Chetvorno, admitted that he wrote most of the article without sources, a clear violation of the consensus of the community described at WP:V and WP:NOR, yet you hold him up like some kind of Good Housekeeping seal of approval. We include material supported by citations, and not that which is based on personal expertise or knowledge. That is not "my position" nor an "interpretation" of policy, it is policy. If you can refute this, then do so. Tell me that WP:NOR does not expressly forbid us from adding uncited material on the basis of personal knowledge. Tell me that what Chetvorno did -- and what you continue to promote -- is precisely that. If you can explain how what I just said is wrong, wihtout spin, lies, rhetorical tricks, logical fallacies, or non-sequiturs, then please, do so. Nightscream (talk) 16:37, 23 August 2022 (UTC)

Edit warring
has reversed 3 attempts to restore this material by 3 different editors (,, myself) over 5 days. recently posted a warning. I have seconded that by reporting it. ~Kvng (talk) 14:18, 19 August 2022 (UTC)
 * I support the 3 editors restoring the material. Nightscream’s drastic cuts cross the line into WP:POINT.--ChetvornoTALK 15:07, 19 August 2022 (UTC)


 * My experience suggests that as only three reverts have been made (so far), that this is unlikely to fly (which is why I didn't raise it - though I would have on the forth revert). However there are other articles where this behaviour is now going on such as Phonograph record and Typecasting. I was initially also going to add Sean Phillips, but this is probably overruled by WP:BLP which specifically prohibits uncited material from such biographies. I think WP:ANI might have been a better venue, but that's just my opinion which is worth exactly what you paid for it. 86.181.0.154 (talk) 16:49, 19 August 2022 (UTC)


 * I would have also reverted Nightscream's drastic cuts and, as an interim measure, applied the combination of section templates and general references I described here, but I felt that would only exacerbate Nightscream's edit warring. - LuckyLouie (talk) 17:01, 19 August 2022 (UTC)
 * Nightscream has reverted three editors in a fight for these changes which are not supported by any of the editors who have participated in the discussion here. Behavior doesn't have to meet WP:3RR to be considered warring. We'll see. ~Kvng (talk) 18:28, 19 August 2022 (UTC)

Just for the record, Nightscream is still at it. Here and here. As I pointed out to Nightscream on my talk page, the last time I saw this at Alternator in 2018, the two editors removing the uncited material (though uncontentious by consensus) were indefinitely blocked for disruptive editing (and the material is still there - uncited as ever). This being the case, there appears to be the application of double standards. 86.181.0.154 (talk) 14:08, 21 August 2022 (UTC)


 * Yeah, you tried citing that anecdote on your talk page too, and when I questioned you about it, because I was skeptical that it went down as you described, you refused to provide diffs, or even answer it. During that discussion, you twice spoke derisively of editors like me who “quote all manner of policies” for removing uncited material (without explaining how the citations of those policies was wrong), and claimed on the Alternator article, two editors who quoted the same policies when deleting uncited material were indefinitely blocked for disruptive editing, and the uncited material remains in the article. I asked you what was wrong with their citation policies. I asked you if those two editors' activities were deemed disruptive solely because they removed material, or for other reasons instead of/in addition to this, like edit warring. The reason I ask is because I had had discussions elsewhere that indicated that such blocks were unlikely for what I was doing. On Jimbo Wales' tp, for example, one editor told Johnuniq, "Tagging and subsequently removing uncited material is not a problem. Any block you placed (as you threatened Nightscream with) on that rationale would almost certainly be overturned and result in you being asked to justify yourself in front of ARBCOM for abuse of admin tools." Then at the recent discussion at the Village Pump, where it was indicated that this notion of yours did not reflect consensus, as one editor responded to Johnuniq's complaint of my moving to the talk page "good material" by asking him point-blank, "Please explain how any material can be described as 'good' if it is not verified," while another stated that he did "see evidence that the OP [Johnuniq] is a problematic editor." Offhand, I could not find any trace of this episode you described in the Alternator article's edit history or talk page. If there were editors who were blocked, then I'm guessing it was because they committed other actions, like edit-warring, or because unlike myself, they deleted material, rather than move it to the talk page, complete with a diff showing where it was in the article, and made efforts to source some of it as I have.


 * I flat-out asked you about this, asking you if those editors actually deleted that material, moved it to the talk page to spur others to source it, and to do some of that sourcing themselves. But you refused to answer, possibly because you misrepresented this conflict, deliberately omitting key details, and when I called you on your bluff, you knew you couldn't provide diffs that would prove me right. Indeed, you continue to refer to my moves as "deletions", even after I suggested to you that omitting those key details by simply calling my practices "deletion" may cause a reader to incorrectly understand that I've absolutely removed information entirely from the article without any means or avenue for its restoration, which is not accurate or honest. You continued to refuse to address these counterarguments, saying, do not propose to spend my time arguing the point", while simultaneously criticizing me for not adhering to Bold-Revert-Discuss—even though you're the one refusing to discuss my counterarguments.


 * Some of you like to cite "consensus", as if a handful of editors on a talk page constitutes a consensus that allows you to violate policy, and that those who oppose you falsify this by presenting arguments or reasoning that conclusively disagrees with you, that you can just ignore those arguments if there's enough of you on that talk page, rather than engage with those arguments. This is not true, and it's not honest. Bear in mind also that I have not asked others who I know agree with me to join me here. If they did, would you still have "consensus"?) The consensus of the editing community (not just some editors on one talk page) is reflected in its policies, and part of interpreting policy is noting what it says on the site's various policy and guideline pages. You can't do an end-run around site-wide policy simply by having several people agree to do so on a single article's talk page. You have to show how your stated position and arguments is in line with those policies.


 * Over on the Isaac Hempstead Wright article, I had to remove uncited additions of that actor's date of birth several times . Are you going to argue that those editors constituted a "consensus", and that I was edit warring because there were more of them than I?


 * Since WP:NOR makes it clear that material cannot be added on the basis of editors' personal knowledge or expertise, claiming that uncited material cannot be moved to the talk page because editors claim it is "potentially good", violates this policy. If you can show why this is wrong, then please explain how.


 * Please take the time to explain why the underlying reasoning in my position is flawed, which thing I've said is untrue. Don't just argue the same position over and over because you don't want to change it. If you can argue that adding and keeping large swaths of uncited material/original research to articles, which Chetvorno admitted they did in this article, then do so. Otherwise, stop complaining that I'm not engaging in "discussion", as more than one of you have mendaciously stated. If you continue to do this, your actions will simply be tacitly confirmed as serial policy violations, as it was not only determined at ANI that my moving of uncited material and undoing your reverts was not a violation, but that the conduct that in which Kvng engaged in order to get his way was deemed inappropriate, which it clearly was.


 * I've held off on doing more moves of articles that have passed the one-month mark in the past few days, so you can respond. But if you continue to employ the "indirect" method of responding, then I'm not going to bother continuing to do so. Please falsify my arguments, or acknowledge that your actions violate policy, and resolve to do the work of sourcing that material as you restore it to articles. Nightscream (talk) 16:37, 23 August 2022 (UTC)

WP:TLDR 86.181.0.154 (talk) 16:31, 25 August 2022 (UTC)


 * +1, please try again ~Kvng (talk) 17:23, 25 August 2022 (UTC)


 * If you are indicating that you won't read something that is the equivalent of a two-page Word document, which is needed to debunk the numerous logical fallacies, lies, and non-sequiturs that multiple serial policy violators have promulgated on multiple discussion pages recently, which cannot be done in the span of a soundbite, then the problem isn't the length of my post. It's that in addition to thinking policies and guidelines don't apply to you, that you're too either too lazy or illiterate, or know that you can't falsify my statements. Uttering a ridiculous canard like "Consensus is more important than policy" takes little time, but explaining why it's bunk -- along with addressing all the other various examples of corruption you've collectively exhibited -- takes longer. It's probably why, as it's been observed, that lies travel faster than truth.


 * Falsify what I've said. Or stop whining to me that I won't "discuss" things with you. Other members of the community have already called you on your practices and your threats are unacceptable. Either explain why my reasoning above is not sound, or I'm done wasting my time with you. Nightscream (talk) 17:33, 25 August 2022 (UTC)
 * No, I'm not going to read something that starts with a screed. Please WP:FOC. ~Kvng (talk) 17:36, 25 August 2022 (UTC)


 * Nightscream, long emotional screeds arguing how you are right and everyone else is wrong and a liar are counterproductive. How about this as an alternative to leaving out huge swaths of the article until someone undertakes the laborious job of fitting each general reference to a particular section of text. Would you agree to:
 * Replacing inline ‘citation needed’ tags after each sentence with unreferenced section templates in each section.
 * Adding WP:GENREF (I listed here.
 * - LuckyLouie (talk) 19:20, 25 August 2022 (UTC)
 * Agree with LuckyLouie. This ham-fisted mass deletion/WP:POINTY has (gone) far enough. Should be WP:BRDed and we can start from there with the suggested templates. Fountains of Bryn Mawr (talk) 20:10, 25 August 2022 (UTC)
 * @Fountains of Bryn Mawr, @LuckyLouie, please, do revert these changes if you want to discuss them further before they become permanent. Three of us have already tried, but the more the merrier. ~Kvng (talk) 17:54, 27 August 2022 (UTC)


 * The bottom line here is that Nightscream alone is right and everybody else is wrong (and this has been said at other venues as well) and is determined to resort to wikilawyering to his hammer home his disruption.


 * And I still haven't read the wall o' text and have no intention of doing so. 86.181.0.154 (talk) 11:52, 26 August 2022 (UTC)
 * Also, the the WP:LAWYERING is working and they are WP:WINNING. ~Kvng (talk) 13:10, 26 August 2022 (UTC)


 * What is being overlooked here is that Wikipedia as a project is a collaborative venture not in the WP:OWNERship of one individual. Yes, there are policies in place to stop disruptive editing, but part of the point of collaboration is that policy can be, to a greater or lesser extent, overruled where there is clear consensus on the article talk page to do so. The gutting of this (and other) articles because content, though well established as correct, not being fully referenced is a case in point. There is a clear near unanimous consensus above that the unreferenced material should be restored as it is accepted, by that consensus, that it is correct without further proof.


 * I believe it would be worth starting a 'Request for Comment' on this issue. As an IP, I cannot initiate one, but am willing to participate should someone else choose to do so. 86.181.0.154 (talk) 13:20, 27 August 2022 (UTC)
 * An RFC here may or may not stick. It certainly would not resolve the general issue of whether (re)moving uncontroversial uncited material is disruptive. I'm not sure what is the best venue to try and work this out. It is not my idea of fun and I don't expect, given Wikipedia's general slide towards deletionism, I'm going to be satisfied with the outcome. ~Kvng (talk) 15:09, 27 August 2022 (UTC)


 * Nightscream is definitely WP:NOTHERE to "collaboratively build an encyclopedia", so should be blocked on this ground alone. 86.181.0.154 (talk) 16:07, 27 August 2022 (UTC)
 * That was one administrator's take on it. But at least one other did not agree. ~Kvng (talk) 17:47, 27 August 2022 (UTC)

I have gone ahead and partially reverted the article (to as edited by Kvng at 14:36, 18 August 2022) per WP:BRD, LuckyLouie, and no further comment above. Most of the content is WP:LIST and does not need citation per say and is notable and already cited (at its parent article). Overall gutting articles, breaking syntax, and making them generally unreadable seems to be and exercise in WP:POINTY. Fountains of Bryn Mawr (talk) 19:11, 27 August 2022 (UTC)
 * Thanks, also would have been very difficult to work on sourcing with text split between article and Talk page. --ChetvornoTALK 23:59, 28 August 2022 (UTC)


 * "The bottom line here is that Nightscream alone is right and everybody else is wrong."
 * Wrong. The point is that the consensus of the editing community is reflected in Wikipedia's policies (as it states right here), but you seem to think that they are wrong, and that you can get away with ignoring those policies is not by overturning them, but by assembling several editors on one talk page, and that somehow constitutes the "consensus". It does not, and I explained above how this idea is bunk. Your reaction is to refuse to answer, and employ all manner of excuses for not doing so, because you can't admit that you can't falsify any of my counterarguments.


 * I have alerted administrators to your continued campaign to ignore Wikipedia's core policies.


 * And btw, bear in mind that when Kvng attempted to report me at ANI my talk page moves and reverts were determined to be "no violation". Nightscream (talk) 01:11, 29 August 2022 (UTC)


 * You have mis-stated the facts - the characteristic resort of someone who is firmly in the wrong. Kvng reported you to WP:ANEW - a completely different venue from WP:ANI handling completely different issues. As I predicted above, there was no violation but only because you had made only three reverts to this article. Had you made a fourth, that would have crossed a line and you may well have been blocked. The issues that you claim are not included in the exceptions to the 3RR rule (WP:3RRNO), which should tell you something.


 * Oh, and a number of editors who agree with each other is a consensus, even if you don't like what they are agreeing to (this is a collaborative project whether you like it or not). And what is more, it seems another administrator is weighing in against you on Daniel Case's talk page underlining my point in the previous paragraph and adding to the consensus. It would be wise of you at this point to drop the stick and back slowly away from the carcass. 86.181.0.154 (talk) 12:21, 29 August 2022 (UTC)
 * This pattern continues. I've created a list of articles I know are affected. Please add any others you may be aware of. ~Kvng (talk) 03:45, 30 August 2022 (UTC)


 * It's also worth pointing out that Nightscream's continued assertion that both you and Chetvorno are a "policy violator" or "serial policy violator" is a sustained and repeated personal attack. He has also attacked Johnuniq by stating that "Johnuniq is continuing his anti-WP:V vendetta". Contributors are required to comment on the article or its content but are not permitted to attack other contributors. Nightscream proposed WP:ANI above. considering the traction that this is getting here and elsewhere, it might be a good idea.


 * Oh, and I have expanded your list somewhat. Or I though I had until a huge edit conflict clobbered it. Seems to have swept up my offerings anyway. 86.181.0.154 (talk) 16:40, 30 August 2022 (UTC)
 * Sorry about that. added a bunch and then I resorted the lists. The browser back button is surprisingly useful during edit conflicts. ~Kvng (talk) 19:38, 30 August 2022 (UTC)

Nightscream has been repeatedly, removing text from the article again, while several editors are working on citing. Having the article text split with some on the Talk page makes it hard to do the sourcing he claims to want. --ChetvornoTALK 01:38, 4 September 2022 (UTC)
 * Unfortunately the diffs are hard to follow due to fiddling with spaces and reference formats. Nevertheless I would recommend taking the trouble to restore just a couple of items that were removed with an edit summary indicating that they are going to be worked on in the next week. Then they need to be fixed with citations in that week. That is, don't restore everything at the moment. Johnuniq (talk) 02:42, 4 September 2022 (UTC)

Nightscream reported to WP:ANEW (again), this time for nine reverts of which the last four are within ten hours violating the three revert rule. So who is the policy violator now? 86.181.0.154 (talk) 13:12, 4 September 2022 (UTC)


 * Regarding Nightscream's claim that citations MUST be supplied, the guideline WP:V says only that information in articles "must be verifiable." Widely known facts and basic elementary statements about the topic will always be verifiable . Any and every textbook about radio would be able to verify the facts.
 * Only disputed facts must be verified with a citation. The previous tagging action is tendentious: going around adding "citation needed" tags to text describing basic topic knowledge. Binksternet (talk) 18:16, 4 September 2022 (UTC)


 * There is no such passage at WP:V or anywhere else that states that only disputed facts must be verified with citations. At WP:BURDEN it states: "All content must be verifiable. The burden to demonstrate verifiability lies with the editor who adds or restores material, and it is satisfied by providing an inline citation to a reliable source that directly supports the contribution." Nightscream (talk) 13:27, 6 September 2022 (UTC)


 * But it is the case that WP:V does not require every sentence to be inline cited. Now it's possible to force inline citing on everything by challenging everything, but it is not necessary to take such action.  That imo is gaming the system and deleting stuff wholesale as a result is a highly disruptive thing to do.  A more collegial approach would be to first attempt to find citations yourself in the spirit of WP:BEFORE.
 * WP:V states When tagging or removing material for lacking an inline citation, please state your concern that it may not be possible to find a published reliable source, and the material therefore may not be verifiable. That is, tagging or removal of material should be a result of a real concern over its accuracy, not simply because it is uncited.  Further, in a footnote, Some editors object to others making chronic, frequent, and large-scale deletions of unsourced information, especially if unaccompanied by other efforts to improve the material.  You might want to consider whether that policy is talking to you. SpinningSpark 09:07, 7 September 2022 (UTC)


 * Precisely. WP:V only requires such material to be verifiable but not necessarily inline referenced if it is generally accepted as true and the discussion here shows universal agreement that it is factual. The stuff that Nightscream has deleted is easily verifiable.


 * It is interesting to note that Nightscream wholesale deletes it, but makes zero attempt to reference it himself but expects everyone else to do the spade work. With that and his repeated threats that he will get anyone who disagrees with him on his talk page blocked is the typical behaviour of a bully. My analysis of the way Nightscream interacts with other users here, and elsewhere, leaves me with a very real impression that we are dealing with a child or at best a very immature adult - but definitely someone who has problems interacting with others. Whatever, he still has no intention of cooperating with others at all, let alone to build an encyclopaedia . 86.181.0.154 (talk) 10:19, 8 September 2022 (UTC)

"...please state your concern that it may not be possible to find a published reliable source, and the material therefore may not be verifiable..."

WP:NOR makes it plain that editors cannot add material based on their own personal knowledge, and Chetvorno admitted here that he has written entire articles on this basis. For this reason, we have no way to trace that material to its point of origin. The burden is on the editor to indicate the source, and not on others to find sources for material when they have no way of knowing if it's valid or not. This is why I fact-tag uncited material and then move it to the talk page, and the validity of this practice is precisely and explicitly the point that the admins on the discussion upheld in that noticeboard discussion last September. Do you dispute this?

"...tagging or removal of material should be a result of a real concern over its accuracy, not simply because it is uncited." That does not reflect the editing practices of the community at large, as can be easily observed by looking at editing and citation patterns, policy pages, discussions like the aforementioned one I linked to above, etc.

"...especially if unaccompanied by other efforts to improve the material."

And since I have often made those efforts in many instnaces (like here, to point to one example), your point is moot, as is 86.181.0.154's bald-faced lie to the contrary. Nightscream (talk) 19:28, 30 April 2023 (UTC)


 * Your going off on a post from 8 months ago because? Fountains of Bryn Mawr (talk) 19:57, 30 April 2023 (UTC)