title: Civil defense siren

text: Most minaret speakers are used as sirens. The purpose of warnings is to notify the population of a danger that threatens their lives. Individuals must go to shelters or their homes, lock doors and windows, take appropriate protective actions, and listen through the radio and television for instructions of civil defense.


title: Civil defense siren

text: Turkey used to have mechanical sirens in Istanbul until before around the early 2000s, when most of them were decommissioned and minaret speakers were most commonly used instead. Even though the main models of the warning speakers are unknown, there is a slightly common presence of Federal Signal and Hörmann, despite very rare cases of some Elektror or Siemens models remaining. They test during the memorial of Ataturk's death and often sound off for common emergencies such as tornadoes, chemical plant issues or incoming enemy attack.


title: Civil defense siren

text: China has sirens located in most cities and towns, particularly those located in or near disputed territories. If the state declares a state of emergency due to attacks or invasion, or when there is a very high risk of military conflict, sirens will warn the public of possible attacks or invasion. The sirens are controlled by the People's Liberation Army.


title: Civil defense siren

text: There are annual or semi-annual test runs, often occurring on commemorative dates that are associated with the Second Sino-Japanese War. For example, Nanjing annually tests air raid sirens at 10 a.m. on 13 December, followed by a moment of silence to commemorate the Nanking Massacre. There have also been some commemorative tests during the memorial periods of major disasters, such as on 19 May 2008 in memory of victims of the 2008 Sichuan Earthquake.


title: Civil defense siren

text: Taiwanese civil defense sirens are erected on police stations and commanded by the nation's Civil Defense Office (). The government issues air raid warnings, as well as tsunami warnings, through the sirens in conjunction with their own Public Warning System that utilizes 4G LTE cell signals. The Taiwanese government also holds annual air-raid drills called Wan-an drills () so the populace can be familiar with what to do in an air raid, given the high risk of war with neighboring Mainland China.


title: Civil defense siren

text: Mumbai has around 200–250 functional sirens. The government is planning to change the system by incorporating modern wireless and digital technology in place of the present landline switching system.


title: Civil defense siren

text: In Mumbai civil defence, sirens were used during the Indo-Pakistan wars of 1965 and 1971, warning civilians about air raids by the Pakistan Air Force. At night, sirens were also used to indicate blackouts, when all lights in Mumbai were switched off. Daily tests of the sirens at 9 a.m. were recently reduced to once per month. They are controlled by the Regional Civil Defence Control Center, Mumbai, with input from Indian Defence Services. Sirens are also used to denote a minute's worth of silence on special occasions.


title: Civil defense siren

text: Singapore currently has a network of 284 stationary sirens named the Public Warning System which warns the entire country of air raids, as well as human-made and natural disasters (except earth tremors). Singapore's sirens are tested at noon on the first day of every month. During the test, the sirens sound a light cheerful chime instead of any of the three signals. The sirens look very similar to the ECN3000 Israel version.


title: Civil defense siren

text: Nearly all towns and cities are equipped with civil defense sirens in case of natural disasters or missile attacks from North Korea. South Korea holds civil defense drills every month to prepare for such scenarios.


title: Civil defense siren

text: Austria is fully covered with an operational air-raid siren system consisting of 8,203 devices as of 2012. They are tested weekly at noon on Saturdays (except in Vienna) with the signal, a 15-second continuous tone. Every year on the first Saturday of October, the whole range of alarm signals (with the exception of the fire alert) is sounded as a system test () and to familiarize the population with the signals.


title: Civil defense siren

text: Belgium used to test its air raid sirens every first Thursday of the trimester (three-month period). Sirens are Sonnenburg Electronic sirens. When the air-raid sirens are tested, the message or is broadcast every time the sirens sound. There are 540 sirens all across the country. A non-audible test was performed every day, and the last test occurred on 4 October 2018. Afterwards, the network was decommissioned. The sirens remain around nuclear facilities, but no tests are performed. The official recommendation is that people subscribe to BE-Alert, a system where information is provided via SMS, e-mail or phone.


title: Civil defense siren

text: Bulgaria has over 4000 sirens deployed around in the country, especially Sofia. These are likely used to warn the peaceful Bulgarian population of earthquakes. Sirens were first installed during the WW2 times to warn the public of incoming attacks by the Nazi Germany, these were replaced by electronic ones during the 1990's. Sirens are tested on the first Wednesday of June every year to see if they're functioning properly. The public is informed about the test earlier on TV, radio or press so that it doesn't cause mass panic among the peaceful Bulgarians citizens. Sirens are being mainly electronic ones (German made type ECN units or other high powered speaker systems on top of public buildings). The signals may include - attack (a 1 minute wailing tone used to indicate an incoming danger) and alert (sometimes referred to as the "all clear" signal which is a continuous single tone). Strongest tremors in Bulgaria are quite rare, so a special earthquake warning system is not needed.


title: Civil defense siren

text: The Czech Republic has around 6,000 sirens. Within these 6,000 sirens which include mechanical sirens and electronic sirens, are tested every first Wednesday of the month. There are three warning signals, which are accompanied by a verbal message in Czech and usually with an English and German translation on electronic sirens. There is also an emergency broadcast on TV channels, maintained by Česká televize, and radio channels, maintained by Český rozhlas.


title: Civil defense siren

text: There are 1,078 electronic warning sirens have been installed in Denmark by HSS Engineering. The sirens are placed on the tops of buildings or on masts. This warning system makes it possible to warn the populations of all urban areas with more than 1,000 inhabitants. This means that about 80% of Denmark's population can be warned using stationary sirens. The remaining 20% are warned by mobile sirens mounted on police cars. The function of the sirens is tested every night, but does not produce any sound. Once every year, on the first Wednesday of May at 12:00, the sirens are tested with sound.


title: Civil defense siren

text: A general alarm consists of a repeating 1-minute sound, made up of tones that ascend for 7 seconds and descend for 7 seconds. The end of danger is signaled by a 1-minute continuous tone. Warning sirens are tested on the first Monday of every month at noon. The testing alarm is shorter than the general alarm (only lasting for 7 or 14 seconds) and may be a flat tone. The sirens are tested on the first Monday of every month at 12:00.


title: Civil defense siren

text: In France, the emergency population warning network is called the (RNA). The system is inherited from the air raid siren network () developed before World WarII. It consists of about 4,500 electronic or electromechanical sirens placed all over France. The system is tested each month at noon on the first Wednesday. The most common siren type is the electromechanical KM Europ 8 port single tone siren. These sirens have a very characteristic sound: a very fast wind-up and a lower pitch than most sirens (the pitch is comparable to a STL-10 on a lower frequency resulting on a lower pitch). A recording of these sirens was used in the movie "Silent Hill".


title: Civil defense siren

text: In Germany, the ('warning authorities') were closed in the 1990s after the threat of the Cold War was over, since the ability to alert the public was then considered unnecessary. As the civil defense sirens were also frequently used to alert volunteer firefighters, many sirens were sold to municipalities for a symbolic price; others were dismantled. In the 2000s, it was realized that the ability to warn the public is not only necessary in cases of war, but also in events like natural disasters, chemical or nuclear accidents, or terrorist attacks. As a result, some cities like Düsseldorf and Dresden began to rebuild their warning sirens. In Hamburg, the sirens are still operational. They also warn the public during storm surges; for instance, all towns in the Moselle Valley continue to operate and test their warning sirens. The majority of operational sirens in Germany are either electric-mechanical type E57 or electronic sirens.


title: Civil defense siren

text: There are no precise official numbers as to how many sirens there used to be, as most of the documents regarding the system's construction and upkeep have been disposed of after the Cold War ended. However, estimates place the number of operational sirens during the system's peak at around 80,000 in West Germany alone. Accounts as to how many of those sirens are still in operation vary significantly depending on the source. The most prominent German company regarding manufacturing and maintenance of sirens, Hörmann Industries, states on its website that they are in charge of maintaining over 60,000 sirens. Granted, that includes mobile sirens that can be mounted on vehicles, but one can deduct from this information that there could be at least around 50,000 stationary sirens still in operation today, many of the once electro-mechanical sirens having been replaced with newer electronic models.


title: Civil defense siren

text: During World WarII, Berlin's air raid sirens became known by the city's residents as "Meier's trumpets" or "Meier's hunting horns" due to Luftwaffe chief Hermann Goering's boast that "If a single bomb ever falls on Berlin, you can call me Meier!".


title: Civil defense siren

text: Hungary has sirens since World War 2 to warn of the air raids, this system of sirens were consisted of "Fm Si 41" sirens, which are Hungarian made, but under the license of the German "Siemens-Schuckert". There were 2 more type of sirens: Elbtalwerk L335/L345 and Elektror L1. Later in the Cold War-era, there was a lot of sirens got placed in areas, which didn't had sirens before, later in the 70s, they slowly started replacing the WW2-era siren system. However this was a downgrade, the Cold War-era sirens had control panels, which didn't able to remotely control the sirens, so if a town had like 34 sirens, the Civil Defense had to go to all of the sirens and turn them on locally. The original "Siren Program" is kinda abandoned by now, however in 2011, they did a "Nationwide Civil Defense Drill", this was consisted of the testing of all the 2500 sirens, placed all over the county. After this, they started to removing the sirens, by every year, the number of sirens are going down. There are only a few counties left, which still operate the old sirens:


title: Civil defense siren

text: -Győr-Moson-Sopron County: Testing, Maintaning the big town's sirens, they randomly do this on villages too.


title: Civil defense siren

text: -Komárom-Esztergom County: They tested, maintaned all of the county's sirens up until 2014, when a few cities got a new siren system (MoLaRi).


title: Civil defense siren

text: The LTTR (Citizen Informing and Alarming) is a siren system, which got installed in a 30 km distance of the Paks Nuclear Powerplant to warn citizen's about a possibly emergency.


title: Civil defense siren

text: The MoLaRi systems are built near the zones, which has facilities/factories working with hazard materials.


title: Civil defense siren

text: • Borsod-Abaúj-Zemplén county: Kazincbarcika, Berente, Sajószentpéter, Sajóbábony, Tiszaújváros, Oszlár, Tiszapalkonya


title: Civil defense siren

text: Siren Signals (Applies to MoLaRi, Electro-mechanical sirens): -6 second going up and down signal for 1x time(Growl Test)


title: Civil defense siren

text: Note: They always announce every siren's test on local media, on the newer sirens, they also do voice announcements: Attention it's a test, attention it's a test! Figyelem ez próba, Figyelem ez próba!


title: Civil defense siren

text: The Italian War Ministry began installing air raid sirens and issuing air defence regulations in 1938. Production was entrusted to La Sonora, founded in 1911 and still active today.


title: Civil defense siren

text: During World WarII, every town had a siren, and several were present in each large city. Even after the danger of bombings had ended, they were kept to provide warning in case of any threat (e.g. high water in Venice).


title: Civil defense siren

text: As of 2015, some of them still survive. For instance, as many as 34 have been located in Rome using crowdsourcing. Up until the 1980s, they underwent routine maintenance and sounded at noon.


title: Civil defense siren

text: Additionally, the Protezione Civile (Civil Protection) operates sirens to warn the public in case of a threat to the citizen population. Protezione Civile also provides transport needs and military defence for the Government of Italy. These defence systems were put in place in the 1990s and are occasionally still used today.


title: Civil defense siren

text: The Netherlands tests its air-raid sirens once per month, on the first Monday at noon, to keep the public aware of the system. There are about 4,200 sirens placed all across the country.


title: Civil defense siren

text: In March 2015 it was announced that, due to high maintenance costs, the sirens will be taken out of service by the end of 2020. The government has implemented a Cell Broadcast system called NL-Alert, compliant to the mandatory European regulation EU-Alert, to replace the sirens by 2021. However, as of early 2022, the sirens will continue to be heard until another decision has been made.


title: Civil defense siren

text: Norway has about 1,250 operational sirens (mostly Kockums air horn units rather than motorized sirens), primarily located in cities. Three different signals are used:


title: Civil defense siren

text: The sirens are tested twice each year, at noon on the second Wednesday of January and June. As of 2014, only the '"critical message" signal is used during tests. Previously, the signal tested in June would use the "air raid" and "all clear" signals. The latter two are no longer used in peacetime.


title: Civil defense siren

text: There are also sirens in the Storfjord area in Møre og Romsdal county to warn about an avalanche from the mountain Åkerneset. These sirens are not operated by Norwegian Civil Defense department; instead, they are operated by Åksnes/Tafjord Beredskap. These sirens can be found in the villages of


title: Civil defense siren

text: Lithuania operates sirens from the Cold War mainly in suburban areas of big cities such as Vilnius, Klaipeda, Kaunas, etc. The most common models are Elektror, Siemens and Hörmann, even though Federal Signal is not too rare in these areas. These sirens can be found in fire stations, factories, police stations and city halls. The attack and all clear signal is used for tests even though tests aren't as frequent as in other areas across Eastern Europe. They soundnoff in case of fires, chemical issues, floods, incoming enemy attack, etc. Testing date for most areas is most likely yearly.


title: Civil defense siren

text: Portugal has hundreds of sirens placed across the country. Urban areas most likely use a few electronic sirens even though the presence of warning sirens is more common in suburban or rural areas, where fire stations use them for fire calls. These kinds of sirens are dual-tone and mechanical and are the most common kind of warning siren in Portugal. Between the 2000s and the early 2010s, a few fire sirens were decommissioned due to maintenance upkeep even though most of them remain active.


title: Civil defense siren

text: In Romania, civil defense sirens have been used since the early 1930s. Originally, each street had a small siren on top of a high-rise building, which could be powered mechanically. During World WarII, the sirens had a single continuous tone to warn of an air strike.


title: Civil defense siren

text: Throughout the Cold War, larger sirens were manufactured locally and installed on various public buildings and residences. The sirens were able to transmit a comprehensive variety of tones, each with a different meaning such as a chemical disaster, an earthquake, a flood, or an imminent air or nuclear strike; each of these tones required the population to either move to higher ground or an ABC shelter. An "all clear" signal was played after the area had been deemed safe for the general public.


title: Civil defense siren

text: Since the 1990s, civil defense sirens have been replaced by electronic sirens and the procedure has been simplified. As of 2013, there are four playable tones: a natural disaster warning, an upcoming air/nuclear strike, an imminent air/nuclear strike, and an "all clear" signal. Taking shelter is no longer a legal requirement, although ABC shelters are still operational.


title: Civil defense siren

text: In August 2017, Romanian authorities started to perform monthly defence siren tests. The first such test took place on 2 August 2017 and is scheduled to be repeated on the first Wednesday of each month, between 10:00 and 11:00am local time. Such tests have been stopped in the wake of the COVID-19 pandemic.


title: Civil defense siren

text: During the siege of Leningrad, the radio network carried information for the population about raids and air alerts. The famous "metronome" went down in the history of the siege of Leningrad as a cultural monument of resistance of the population.


title: Civil defense siren

text: At that time, there were more than 1 thousand loudspeakers and 400 thousand radio streams operating in the city. If there were no broadcast programs, then the metronome was broadcast with a slow rhythm of 50-55 beats per minute. The network was switched on around the clock, which allowed the population and services to be confident in the operation of the network. By order of the MPVO headquarters, the duty officer of the Central station of the radio network interrupted the broadcast of the program, turned on an electric player with a record of the alarm text. This record was supplemented by 400 electric sirens. At the end of the recording, the metronome was switched on with a rapid rhythm of 160-180 beats per minute. When the danger was over, the electric player was switched on again by order of the staff, and the alarm was sounded in the streets and houses, accompanied by the sound of fanfares.


title: Civil defense siren

text: Slovenia has 1,563 operable civil defence sirens. Most of them are electronic sirens, although there are some mechanical ones. Civil defence sirens are mounted on fire stations, town halls, or other structures.


title: Civil defense siren

text: Since 1 September 1998, there are two additional siren tones, which are used in certain Slovenian municipalities. The municipalities of Hrastnik and Trbovlje use a special signal (called "Neposredna nevarnost nesreče s klorom") for the immediate danger in case of an accident involving chlorine when there is a danger of chlorine leaks in the environment. The 100 second long signal consists of a 30-second wailing tone immediately followed by a 40-second steady tone and again of a 30-second wailing tone. The municipalities of Muta, Vuzenica, Podvelka, Radlje ob Dravi, Brežice, Krško and Sevnica use a 100-second long wailing signal (named "Neposredna nevarnost poplavnega vala") (consisting of 4-second bursts separated by 4 seconds of silence) for the immediate danger of flash floods, used in case of overflow or collapse of a hydroelectric dam.


title: Civil defense siren

text: When emergencies impact multiple regions at the same time, or the whole country, people are advised to listen to the first channel of the public Radio Slovenia, Val 202, or watch the first or second channel of the public broadcaster RTV Slovenija. Emergencies of smaller extent are announced via regional radio and TV stations.


title: Civil defense siren

text: Until 1 January 1998, air raid sirens were tested each Saturday at noon. The formerly used warning signals were:


title: Civil defense siren

text: Few sirens that were used for civil defence against bombings during the Spanish Civil War are preserved. The Guernica siren has a highly symbolic value because of the impact of the Bombing of Guernica. Barcelona City History Museum preserves one related to the Bombing of Barcelona, and another siren from civil war years is also preserved in Valencia.


title: Civil defense siren

text: The Swedish alarm system uses outdoor sirens in addition to information transmitted through radio and television and sent by text messages and mobile apps. Special radio receivers are handed out to residents living near nuclear power plants. The outdoor system , also known as ('Hoarse Fredrik', alluding to the sound of the siren) to the Swedish population, consists of 4,600 sirens. These sirens were first tested in 1931, and were mounted to cars and bikes sent out by the government. The sirens can be found on tall buildings all around Sweden. They are driven by compressed air in giant tanks, but are successively being replaced by modern electronic sirens which use speakers. The emergency services are also able to send out spoken messages through the new sirens. The outdoor signals used are as follows:


title: Civil defense siren

text: The outdoor sirens are tested four times a year on the first non-holiday Monday of March, June, September, and December at 15:00 local time. The test consists of the general alarm for 2 minutes, followed by a 90-second gap before the "all clear" is sounded.


title: Civil defense siren

text: There are usually around 15 to 20 general alarms, occurring locally, per year. The most common cause of general alarms is fire, specially in situations that involve industries, landfills, and other facilities containing dangerous substances which can create hazardous smoke. The 2018 peak in alarms (54 that year) is attributed to the 2018 Sweden wildfires which alone caused over 20 general alarms. Other possible attributing factors could be the increased public safety awareness after the 2017 Stockholm truck attack.


title: Civil defense siren

text: Switzerland currently has 8,500 mobile and stationary civil defense sirens, which can alert 99% of the population. There are also 700 sirens located near dams. Every year on the first Wednesday of February, Switzerland's sirens are tested to see if they are functioning properly. During this test, general alert sirens as well as sirens near dams are checked. The population is informed of the test in the days leading up to the tests by radio, television, teletext, and newspapers, and the siren tests do not require the population to take any special measures.


title: Civil defense siren

text: The tones of the different sirens are provided on the last page of all phone books as well as on the Internet.


title: Civil defense siren

text: Ukraine has employed civil defense sirens to warn citizens of danger during the 2022 Russian invasion of Ukraine.


title: Civil defense siren

text: These tones would be initiated by the Royal Observer Corps after spotting Luftwaffe aircraft coming toward Britain, with the help of coastal radar stations. The "red warning" would be sounded when the Royal Observer Corps spotted enemy aircraft in the immediate area. The sirens were tested periodically by emitting the tones in reverse order, with the "all clear" tone followed by the "red warning" tone. This ensured the public would not confuse a test with a real warning.


title: Civil defense siren

text: Every village, town, and city in the United Kingdom used to have a network of dual-tone sirens to warn of incoming air raids during World WarII. The operation of the sirens was coordinated by a wire broadcast system via police stations. In towns and cities with a population of over 3,000, powered sirens were used, whereas in rural areas hand-operated sirens were used (which were later put to use as warnings for nuclear attack during the Cold War). At the end of the Cold War in 1992, the siren network was decommissioned, and very few remain. These sirens, mostly built by Carter, Gents, Castle Castings, and Secomak (now Klaxon Signal Co.), have 10 and 12 ports to create a minor third interval (B and D notes) and are probably the world's most recognised World WarII air raid siren sound. Recordings of British sirens are often dubbed into movies set in countries which never used this type of siren.


title: Civil defense siren

text: Around 1,200 sirens remain, mostly used to warn the public of severe flooding. They are also used for public warning near gas or nuclear power plants, nuclear submarine bases, oil refineries and chemical plants. The remaining sirens are a mix of older motor driven models (usually from World WarII), such as the Carter siren manufactured by Carter's of Nelson or the "syren" manufactured by Gent's of Leicester, and Cold War like Castle Castings and Secomak (now Klaxon Signal Co.) and newer electronic sirens like Hormann ECN, Whelen, Federal Signal Modulator, ATI HPSS and COOPER WAVES. Most of them usually tested annually between August and September if they're not in a siren system. They are also used to start and finish silences on Armistice Day and Remembrance Sunday


title: Civil defense siren

text: There was a siren system consisted mainly of Castle Castings and 2 Secomak GP3s for their flood warning system sector. When MoD was decommissioning these systems across the country, Norfolk kept their sector back for flood warning. With the advent of digital services and mobile technology, many local authorities are now retiring their siren networks in favour of contacting people by telephone. In January 2007, proposals to retire a network of sirens in Norfolk were made by the Norfolk Resilience Forum. In November 2007, residents were angered after the sirens had not sounded following a tidal surge in Walcott. In 2008, a review of the current and future role of flood warning sirens was undertaken by Norfolk County Council, after plans to retire them were halted following concerns from nearby residents. Although some of the sirens were initially withdrawn, 40 out of the 57 were eventually temporarily reinstated. Despite this, in July 2010 the flood warning sirens were finally retired in favour of alerting people by telephone, SMS or e-mail. After three years of consultations, the council had failed to demonstrate that refurbishing the sirens would be a worthwhile investment. The whole siren system was completely gone by late 2013, with only 2 sirens remaining, which are both inactive with one of them refurbished and put on display on a beach not far from its original location, and another, in Mundesley Fire Station, just standing there, extremely unlikely to ever sound again.


title: Civil defense siren

text: Lincolnshire, which had one of the largest siren systems in the country consisting of Carters, had 46 sirens based in North Somercotes, Mablethorpe, Boston, Skegness, Spalding and Sutton Bridge, as well as inland at Louth, Horncastle, Middle Rasen and Gainsborough, the areas most at risk of being hit by floods. Following serious flooding in the summer of 2007, investigations took place into how the flood warning system could be improved. The Environment Agency admitted that the warning system in Louth had not sounded early enough. In April 2008, Lincolnshire County Council began to investigate the possibility of replacing the flood warning sirens with mobile phone alerts. A council report in November 2009 described the sirens as being "outdated, in the wrong places and difficult to repair". The sirens were eventually decommissioned in November 2011 and replaced with Floodline.


title: Civil defense siren

text: In January 2010, 13 public warning sirens on the island of Guernsey that had first been installed in 1937 were due to be retired and replaced by text messages. This followed claims by the Home Department that the sirens had "reached the end of their useful working life". The sirens had previously been used to warn of major incidents. From 1950 to 2010, the Civil Defence Committee took responsibility for the sirens, and had tested them annually since 9 May 1979. Members of the public had criticised the decision, and Deputy Janine Le Sauvage claimed that sirens were the only way everyone knew there was an emergency. In February 2010, 40 islanders formed a protest march opposing the proposal to retire the sirens. The campaigners accused the government of not listening to them, as an online petition calling for the sirens to be saved was signed by more than 2,000 people. In April 2010, it was decided to dismantle the public warning system. Emergency planners had proposed to use a new warning system that would contact residents by telephone; however, this was abandoned due to technical limitations and local media and other communication methods are used instead. Only 2 remain in Guernsey, one in Victoria Tower, which sounded off once at around 2017, and another, active for a quarry.


title: Civil defense siren

text: Following severe flooding in Upper Calder Valley in June 2000, the Environment Agency replaced its network of sirens, with eight being placed around Walsden, Todmorden, Hebden Bridge and Mytholmroyd. The network was designed to complement the agency's Floodline service. These sirens became what is now known as the Todmorden Flood Warning System. There are 9 sirens that are part of the system, 5 of them being Secomak, 3 of them being Klaxon and one of them being Carter (which was recently confirmed to be inactive according to the local environment agency).


title: Civil defense siren

text: In November 2010, 36 flood warning sirens in Essex, including nine on Canvey, were retired following concerns from the county council that the system was "no longer fit for purpose". The sirens were due to become obsolete in 2014. Only 5 sirens from the entire system remain, 2 of them in Canvey Island.


title: Civil defense siren

text: In September 2012, new flood warning sirens were installed in the Dunhills Estate in Leeds, as part of flood defence work at Wyke Beck. In January 2014, flood sirens sounded for the first time in 30 years on the Isle of Portland.


title: Civil defense siren

text: Broadmoor Hospital used 13 sirens installed in 1952, which were tested weekly. These were consisted of Secomak CS8s, which weres similar to a Secomak GP8 except the CS8 had coded shutters which could do an alternating hi-lo signal, and if designed to do so, could also do a pulse signal. For emergencies, they sounded the hi-lo and for all clear, they sounded a steady tone. In tests, they would sound the all-clear. In July 2014, plans were put forward to retire 7 of the 13 alarms, which had last been properly activated in 1993. The alarms are located in areas such as Sandhurst, Wokingham, Bracknell, Camberley and Bagshot. In June 2016, the West London Mental Health Trust, who manages the hospital, proposed decommissioning the sirens altogether and replacing them with social media alerts through websites such as Twitter. In December 2019, this entire system was decommissioned, in favour of only one CS8 operating at the site itself for "silent testing" every Monday. The Monday "silent testing" has ceased and the last remaining siren is silenced and quite likely inactive.


title: Civil defense siren

text: A similar siren system in Carstairs, Scotland, called the Carstairs Hospital Siren System, uses 9 sirens, 7 of them being Secomak CS8, 1 being a Klaxon GP8 and 1 being Secomak GP12. The hi-lo signal is rarely used since during emergencies, they sound a continuous tone for 8 minutes and in all clear, they sound a long wail, consisting of 30 seconds startup and alert and a 30 second wind-down 3 times. Test schedule is the third Thursday of every month at 1PM with the all-clear.


title: Civil defense siren

text: There are several sirens in use around Avonmouth near Bristol to warn of chemical incidents from industry in the area. These are known as the Severnside Sirens. These sirens consist of Federal Signal Modulators and two DSAs, which were installed in 1997 for the public. The system is tested every third day of every month at 3PM. This consists of rising tones and a steady pulsing tone, followed by a steady tone for all clear. In emergencies, they will run for as long as the batteries can allow since they are off-grid powered.


title: Civil defense siren

text: In Canada, a nationwide network of Canadian Line Materials sirens was established in the 1950s to warn urban populations of a possible Soviet nuclear attack. This system was tested nationwide twice in 1961, under the codenames Exercise Tocsin and "Tocsin B". The system was maintained until the 1970s, when advancements in military technology reduced the Soviet nuclear missile strike time from 3–5 hours to less than 15 minutes. Sirens can still be found in many Canadian cities, all in various states of repair. In Toronto, for instance, the network has been abandoned to the point where no level of government will take responsibility for its ownership. A handful of sirens still remain in Toronto in older established neighbourhoods:


title: Civil defense siren

text: Sirens have recently been built within 3 kilometers of the Darlington and Pickering nuclear power plants in the province of Ontario. (Both plants are within 30 kilometers of each other.) These sirens will sound in the event of a nuclear emergency that could result in a release of radioactivity. Sirens have also been placed (and are tested weekly) in Sarnia, Ontario due to the large number of chemical plants in the vicinity. These consist mainly of ATI HPSS32 sirens, as well as a Federal Signal Modulator in the rail yards and 3 Thunderbolt 1003s located at the Suncor plant.


title: Civil defense siren

text: Sirens have also been installed in and around the Grey Bruce Nuclear Generating Station. The sirens are on the plant and in the surrounding communities such as Tiverton, Ontario. One notable siren is a Federal Signal Modulator at the Bruce Nuclear Visitor's Centre. The Public Siren network as it is called, consists of mostly Whelens, Modulators, and Model 2s. One of the sirens in this network (a Model 2) is at Tiverton, which is about 10 km from the plant.


title: Civil defense siren

text: Many warning sirens in Ontario, Manitoba, Saskatchewan and Alberta are now used as tornado warning instruments. Smithers, British Columbia uses an old air raid siren as a noon-day whistle. One of the warning sirens was even used as a goal horn for the Quebec Nordiques between the mid 1980s and 1991. Caledonia, Ontario routinely uses an air raid siren to call in their local volunteer firefighters to the fire hall. NOAA Weather Radios in Canada are often used for advance warnings about future severe storms whenever people are at home, at a business or in a car.


title: Civil defense siren

text: In the United States, several sets of warning tones have been used that have varied due to age, government structure, and manufacturer. The initial alerts used during World WarII were the alert signal (a 3–5-minute steady, continuous siren tone) and the attack signal (a 3–5-minute warbling tone, or series of short tone bursts on devices incapable of warbling, such as whistles). The Victory Siren manual stated that when a manual generation of the warbling tone was required, it could be achieved by holding the "Signal" switch on for 8 seconds and off for 4 seconds. In 1950, the Federal Civil Defense Administration revised the signals, naming the alert signal "red alert" and adding an "all clear" signal, characterized by three 1-minute steady blasts with 2 minutes of silence between the blasts.


title: Civil defense siren

text: Beginning in 1952, the Bell and Lights Air Raid Warning System, developed by AT&T, was made available to provide automated transmission of an expanded set of alert signals:


title: Civil defense siren

text: The "yellow alert" and "red alert" signals correspond to the earlier "alert" signal and "attack" signal, respectively, and the early Federal Signal AR timer siren control units featured the "take cover" button labeled with a red background and the "alert" button labeled with a yellow background. Later AF timers changed the color-coding, coloring the "alert" button blue, the "take cover" button yellow, and the "fire" button red (used to call out volunteer firefighters), thus confusing the color-coding of the alerts. In 1955, the Federal Civil Defense Administration again revised the warning signals, altering them to deal with concern over nuclear fallout. The new set of signals were the "alert" signal (unchanged) and the "take cover" signal (previously the "attack" signal). The "all clear" signal was removed because leaving a shelter while fallout was present would prove hazardous.


title: Civil defense siren

text: Sirens began to replace bells for municipal warning in the early 1900s, but became commonplace following America's entry into World WarII. Most siren models of this time were single-tone models which often sounded almost an octave higher in pitch than their European counterparts. Dual-tone sirens became more common in the 1950s, but had been used in some areas since about 1915. During the Cold War, standard signals were used throughout the country for civil defense purposes, referred to as "alert" and "attack." Volunteer fire departments generally used a different siren signal. Many towns, especially in California and New England, used coded air horns or diaphones for fire calls and reserved sirens for civil defense use.


title: Civil defense siren

text: Today, signals are determined by state and local authorities, and can vary from one region to another. The most common tones produced by sirens in the United States are "alert" (steady) and "attack" (wail). Other tones include Westminster Chimes (commonly used for the testing of electronic sirens), hi-lo (high-low), whoop, pulse (pulsing), air horn, and fast wail.


title: Civil defense siren

text: The U.S. federal standard regarding emergency warning signals is defined in FEMA's Outdoor Warning Systems Guide, CPG 1–17, published on March 1, 1980, which describes the Civil Defense Warning System (CDWS) and its warning signals. The language was slightly revised by FEMA's National Warning System Operations Manual, Manual 1550.2 published 03-30-2001:


title: Civil defense siren

text: The most common tone, "alert", is widely used by municipalities to warn citizens of impending severe weather, particularly tornadoes which have earmarked the sirens as "Tornado Sirens". This practice is nearly universal in the Midwest and parts of the Deep South, where intense and fast-moving thunderstorms that can produce tornadoes occur frequently. The "alert" sound is a steady, continuous note. In seaside towns, "alert" may also be used to warn of a tsunami. Sirens that rotate will have a rising-and-falling tone as the direction of the horn changes. The "attack" tone is the rising and falling sound of an air raid or nuclear attack, frequently heard in war movies. It was once reserved for imminent enemy attack, but is today sometimes used to warn of severe weather, tsunamis, or even fire calls, depending on local ordinance.


title: Civil defense siren

text: There is no standard "fire" signal in the United States, and while the use of sirens by volunteer fire departments is still common, it is diminishing. In the dry areas of the American West, residents may be required to shut off outdoor water systems to ensure adequate pressure at fire hydrants upon hearing the signal. The "fire" signal can vary from one community to another. Three long blasts on a siren is one common signal, similar to the signal used by volunteer brigades in Germany and other countries, while other locales use the hi-lo (high-low) signal described above. Some communities, particularly in New England and northern California, make use of coded blasts over a diaphone or air horn for fire signals, reserving the use of sirens for more serious situations. Still others use the "attack" tone as their fire call. Some communities make use of an "all clear" signal, or sound separate signals for fire calls and ambulance runs. Some fire signals in the U.S. are often blasted at least once a day, mostly at noon, to test the system, and are often referred to as "noon sirens" or "noon whistles". These also function as a time tick for setting clocks.


title: Civil defense siren

text: CPG 1-17 recommends that a monthly test be conducted, consisting of the steady "attention" signal for no more than one minute, one minute of silence, and the "attack" signal for no more than one minute. A "growl test" signal is also described by CPG 1–17, when a siren must be tested more than once a month. This is typically a 1-second burst of sound to verify the proper operation of the siren without causing a significant number of people to interpret the test as an actual alert. Many cities in the U.S. periodically sound their sirens as a test, either weekly, monthly, or yearly, at a day and hour set by each individual city.


title: Civil defense siren

text: In the United States, there is no national level alert system. Normally, sirens are controlled on a county or local level, but some are controlled on a state level, such as in Hawaii. Sirens are usually used to warn of impending natural disaster; while they are also used to warn of threats of military attacks, these rarely occur in the United States. Throughout the Great Plains, Midwest, and South, they are typically used to warn the public to take cover when a tornado warning is issued, sometimes even for severe thunderstorm warnings, and very rarely used for anything else. They are generally required in areas within a ten-mile radius of nuclear power plants. In the South and on the East Coast (except for Texas, Maine, Florida and New Hampshire), sirens are used to inform people about approaching hurricanes.


title: Civil defense siren

text: In Pierce County, Washington there is a system of sirens set up along the Puyallup and Carbon River valleys to warn residents of volcanic eruptions and lahars (giant mudslides) from Mt. Rainier.


title: Civil defense siren

text: Coastal communities, especially those in northern California, Oregon, Washington, Alaska, and Hawaii, use siren systems to warn of incoming tsunamis. In 2011, the city of Honolulu created an "Adopt-A-Siren" website for its tsunami sirens. The site is modeled after Code for America's "Adopt-a-Hydrant", which helps volunteers in Boston sign up to shovel out fire hydrants after storms.


title: Civil defense siren

text: Some U.S. volunteer fire departments, particularly in rural areas, use sirens to call volunteers to assemble at the firehouse. This method is being used less frequently as technology advances and local residents within earshot often file complaints with their town boards. Some areas utilize their sirens as a last resort, relying more on cellular and paging technology; however, a decreasing number of rural departments are still outside the range of wireless communications and rely on sirens to activate the local volunteer departments.


title: Civil defense siren

text: Many college campuses in the U.S., especially in the wake of the Virginia Tech shooting, have begun installing sirens to warn students in the event of dangerous incidents. Sirens in the United States have been replaced by NOAA Weather Radios for advance warnings about future severe storms whenever people are inside cars or buildings.


title: Civil defense siren

text: A series of 98 electronic sirens, making up a large-scale public-address system (the "Sydney CBD Emergency Warning System") and including 13 variable-message signs, are installed in the Sydney central business district. While installed in the months preceding the 2007 APEC conference, they are designed to be a permanent fixture and are tested on a monthly basis.


title: Civil defense siren

text: Some large-scale sirens are also deployed, like the Grifco Model 888, Grifco Model 777, or Klaxon SO4, which are used at fire stations for call-outs and at Sydney's beaches for shark alarms. Alarms are also used around prisons for breakouts and at many factories and schools to announce start and finish times.


title: Civil defense siren

text: A siren is located at the Kwinana BP plant south of Perth, which is tested every Monday. It is used to evacuate the plant in case of an emergency and can be heard in Kwinana and certain parts of Rockingham. It can also be used to warn of severe weather and potentially dangerous emergencies on the Kwinana Industrial Strip.


title: Civil defense siren

text: In South Australia, a number of Country Fire Service stations have a siren on or near the station. These are only activated when the brigade are responding to bushfire or grassfire events and for testing. They are not activated for every call, only as a public alert for the presence of bushfires.


title: Civil defense siren

text: As had been in Australia, Electro-mechanical sirens and electronic sirens had been used for alerting the community areas, towns and cities in Australia as in an imminent emergency. Emergency broadcast speakers will be turned on and will be informing important information as the standard emergency warning signal the affected communities within 24 hours.


title: Civil defense siren

text: In Victoria, many Country Fire Authority stations or near the fire station have a siren installed that is used to summon volunteers to an emergency callout, as well as consequently alerting the local community of brigade activity. Due to a variety of siren models in use across the state, there are 2 signals that are used, differentiated by length:


title: Civil defense siren

text: In Melbourne's CBD, there is a set of sirens installed to warn of attack and extreme flooding. These became necessary after the Bourke and Flinders St. attacks, where people were killed as a result of a vehicle purposefully driving into pedestrians.


title: Civil defense siren

text: In Queensland, Whelen Vortex-R4 sirens have been installed as part of the Somerset Regional Council Flood Warning System. At nearby Grantham, Queensland, a Whelen WPS-2906, which features both warning tones and pre-recorded messages provides early warning in the event of flooding. As well, Cairns Regional Council have installed 9 Whelen WPS-2900 series sirens to alert to a dam breach of the nearby Copperlode Falls Dam. A map of the system can be found here, as well as additional information. Other Whelen WPS-2900 series sirens can be found in a few towns around Queensland as well.


title: Civil defense siren

text: Lower Hutt, Napier, Whanganui, and the former Waitakere City area of Auckland each have a network of civil defense sirens. The networks in Lower Hutt and Napier are bolstered by fire sirens that also function as civil defense sirens. Lower Hutt's network is further bolstered by selected industrial sirens that double as civil defence sirens. In the western Bay of Plenty, several fire sirens also serve as civil defense sirens, and there are dedicated civil defense sirens at the Bay Park Raceway in Mount Maunganui, Tokoroa, and Whangamata (which has two). Additionally, Tokoroa, Putaruru, Tirau, and Whangamata have fire sirens serving double duty as civil defense sirens. In the years following the tsunamis of the Indian Ocean earthquake in 2004, Meerkat electronic sirens were installed in all populated areas of the west coast lower than 10 metres.


title: Civil defense siren

text: Warning sounds vary from area to area, including rising and falling notes and Morse code sirens. Communities with volunteer fire brigades use a continuous note on all sirens for civil defense, and a warbling siren on the fire station siren only for fire callouts. Civil defense uses a distinctive "sting" siren that is used by all radio stations nationwide, but is currently only used for civil defense sirens in Wanganui.


title: Civil defense siren

text: Morocco, like other countries, has civil defense sirens in many cities and small towns. Such as the cities of Casablanca, Oujda, Asilah, M'diq,Chefchaouen, Qalaat and Sraghna. Not all cities are equipped with this system. These sirens are found at fire stations and city halls.


title: Civil defense siren

text: These sirens were installed for the first time in Morocco during the period of French and Spanish colonialism, which is still working to the present time, but some of them were dismantled like the Marrakesh siren.


title: Civil defense siren

text: These sirens are spread in urban cities with high population densities (Casablanca's sirens), or in cities and areas threatened by natural disasters such as floods (Eureka's siren), in cities, tourist areas (M'Diq's and Chefchaouen's sirens), and in areas of dangerous industries.


title: Civil defense siren

text: These sirens are rarely used due to the lack of dangers threatening the population, but recently during the quarantine periods of the pandemic, warning sirens sounded in a number of cities such as the city of Oujda to alert the population by the time of the night closure.


title: Civil defense siren

text: These sirens are often used in Morocco during the days of Ramadan, in order to inform the citizens about the arrival of the time of Fotour.


title: Civil defense siren

text: In the past, these sirens were used in small towns to call for volunteer paramedics in emergencies such as fires or cases of drowning.


title: Civil defense siren

text: The state uses alternative means of civil defense sirens in cities that do not have sirens, such as sending warning messages in news bulletins on television or radio, or sending SMS messages to citizens' phone numbers. Police patrol car horns sound as sirens to warn in case of danger.


title: Dale Chihuly

text: Dale Chihuly () (born September 20, 1941) is an American glass artist and entrepreneur. He is best known in the field of blown glass, "moving it into the realm of large-scale sculpture".


title: Dale Chihuly

text: Dale Patrick Chihuly was born on September 20, 1941, in Tacoma, Washington. His parents were George and Viola Chihuly; his paternal grandfather was born in Slovakia. In 1956, his older brother and only sibling George died in a Navy aviation training accident in Pensacola, Florida. Two years later in 1958, Chihuly's father died of a heart attack at the age of 51.


title: Dale Chihuly

text: Chihuly had no interest in continuing his formal education after graduating from Woodrow Wilson High School in 1959. However, at his mother's urging, he enrolled at the College of Puget Sound. A year later, he transferred to the University of Washington in Seattle to study interior design. In 1961, he joined the Delta Kappa Epsilon fraternity (Kappa Epsilon chapter), and the same year he learned how to melt and fuse glass. In 1962, Chihuly dropped out of the university to study art in Florence. He later traveled to the Middle East where he met architect Robert Landsman. Their meeting and his time abroad spurred Chihuly to return to his studies. In 1963, he took a weaving class where he incorporated glass shards into tapestries. He received an award for his work from the Seattle Weavers Guild in 1964. Chihuly graduated from the University of Washington in 1965 with a Bachelor of Arts degree in interior design.


title: Dale Chihuly

text: Chihuly began experimenting with glassblowing in 1965, and in 1966 he received a full scholarship to attend the University of Wisconsin–Madison. He studied under Harvey Littleton, who had established the first glass program in the United States at the university. In 1967, Chihuly received a Master of Science degree in sculpture. After graduating, he enrolled at the Rhode Island School of Design, where he met and became close friends with Italo Scanga. Chihuly earned a Master of Fine Arts degree in sculpture from the RISD in 1968. That same year, he was awarded a Louis Comfort Tiffany Foundation grant for his work in glass, as well as a Fulbright Fellowship. He traveled to Venice to work at the Venini factory on the island of Murano, where he first saw the team approach to blowing glass. After returning to the United States, Chihuly spent the first of four consecutive summers teaching at the Haystack Mountain School of Crafts in Deer Isle, Maine. In 1969, he traveled to Europe, in part to meet Erwin Eisch in Germany and Stanislav Libenský and Jaroslava Brychtová in Czechoslovakia.


title: Dale Chihuly

text: Chihuly donated a portion of a large exhibit to his alma mater, the University of Wisconsin, in 1997 and it is on permanent display in the Kohl Center. In 2013 the university awarded him an Honorary Doctorate of Fine Arts.


title: Dale Chihuly

text: In 1971, with the support of John Hauberg and Anne Gould Hauberg, Chihuly co-founded the Pilchuck Glass School near Stanwood, Washington. Chihuly also founded the HillTop Artists program in Tacoma, Washington at Hilltop Heritage Middle School and Wilson High School.


title: Dale Chihuly

text: In 1976, while Chihuly was in England, he was involved in a head-on car accident that propelled him through the windshield. His face was severely cut by glass and he was blinded in his left eye. After recovering, he continued to blow glass until he dislocated his right shoulder in 1979 while bodysurfing.


title: Dale Chihuly

text: In 1983, Chihuly returned to his native Pacific Northwest where he continued to develop his own work at the Pilchuck Glass School, which he had helped to found in 1971. No longer able to hold the glassblowing pipe, he hired others to do the work. Chihuly explained the change in a 2006 interview, saying "Once I stepped back, I liked the view", and said that it allowed him to see the work from more perspectives, enabling him to anticipate problems earlier. Chihuly's role has been described as "more choreographer than dancer, more supervisor than participant, more director than actor". "San Diego Union-Tribune" reporter Erin Glass wrote that she "wonders at the vision of not just the artist Chihuly, but the very successful entrepreneur Chihuly, whose estimated sales by 2004 was reported by "The Seattle Times" as $29 million."


title: Dale Chihuly

text: Chihuly and his team of artists were the subjects of the documentary "." They were also featured in the documentary "Chihuly in the Hotshop," syndicated to public television stations by American Public Television starting on November 1, 2008.


title: Dale Chihuly

text: In 2010, the Space Needle Corporation submitted a proposal for an exhibition of Chihuly's work at a site in the Seattle Center, in competition with proposals for other uses from several other groups. The project, which sees the new Chihuly exhibition hall occupy the site of the former Fun Forest amusement park in the Seattle Center park and entertainment complex, received the final approval from the Seattle City Council on April 25, 2011. Called Chihuly Garden and Glass, it opened May 21, 2012.


title: Dale Chihuly

text: In 2006, Chihuly filed a lawsuit against his former longtime employee, glassblower Bryan Rubino, and businessman Robert Kaindl, claiming copyright and trademark infringement. Kaindl's pieces used titles Chihuly had employed for his own works, such as Seaforms and Ikebana, and resembled the construction of Chihuly's pieces. Legal experts stated that influence on art style did not constitute copyright infringement. Chihuly settled the lawsuit with Rubino initially, and later with Kaindl as well.


title: Dale Chihuly

text: Regina Hackett, a "Seattle Post-Intelligencer" art critic, provided a chronology of Chihuly's work during the 1970s, 1980s, and 1990s:


title: Dale Chihuly

text: For his exhibition in Jerusalem, Israel, in 2000, in addition to the glass pieces, he had enormous blocks of transparent ice brought in from an Alaskan artesian well and formed a wall, echoing the stones of the nearby Citadel. Lights with color gels were set up behind them for illumination. Chihuly said the melting wall represented the "dissolution of barriers" between people. This exhibit holds the world record for most visitors to a temporary exhibit with more than 1.3 million visitors.


title: Dale Chihuly

text: Chihuly's largest permanent exhibit is at the Oklahoma City Museum of Art. Other large collections can be found at the Morean Arts Center in St. Petersburg, Florida, and Chihuly Garden and Glass in Seattle, Washington.


title: Dale Chihuly

text: Chihuly also maintains two retail stores in partnership with MGM Resorts International, one at the Bellagio on the Las Vegas Strip, and the other at the MGM Grand Casino in Macau.


title: Dale Chihuly

text: Chihuly's art appears in over 400 permanent collections all over the world, including in the United States, Canada, England, Israel, China, Singapore, the United Arab Emirates, and Australia.


title: Hardboiled

text: Hardboiled (or hard-boiled) fiction is a literary genre that shares some of its characters and settings with crime fiction (especially detective fiction and noir fiction). The genre's typical protagonist is a detective who battles the violence of organized crime that flourished during Prohibition (1920–1933) and its aftermath, while dealing with a legal system that has become as corrupt as the organized crime itself. Rendered cynical by this cycle of violence, the detectives of hardboiled fiction are often antiheroes. Notable hardboiled detectives include Dick Tracy, Philip Marlowe, Mike Hammer, Sam Spade, Lew Archer, Slam Bradley, and The Continental Op.


title: Hardboiled

text: The style was pioneered by Carroll John Daly in the mid-1920s, popularized by Dashiell Hammett over the course of the decade, and refined by James M. Cain and by Raymond Chandler beginning in the late 1930s. Its heyday was in 1930s–50s America.


title: Hardboiled

text: From its earliest days, hardboiled fiction was published in and closely associated with so-called pulp magazines. Pulp historian Robert Sampson argues that Gordon Young's "Don Everhard" stories (which appeared in "Adventure" magazine from 1917 onwards), about an "extremely tough, unsentimental, and lethal" gun-toting urban gambler, anticipated the hardboiled detective stories. In its earliest uses in the late 1920s, "hardboiled" did not refer to a type of crime fiction; it meant the tough (cynical) attitude towards emotions triggered by violence.


title: Hardboiled

text: The hardboiled crime story became a staple of several pulp magazines in the 1930s; most famously "Black Mask" under the editorship of Joseph T. Shaw, but also in other pulps such as "Dime Detective" and "Detective Fiction Weekly". Consequently, "pulp fiction" is often used as a synonym for hardboiled crime fiction or gangster fiction; some would distinguish within it the private-eye story from the crime novel itself. In the United States, the original hardboiled style has been emulated by innumerable writers, including James Ellroy, Paul Cain, Sue Grafton, Chester Himes, Paul Levine, John D. MacDonald, Ross Macdonald, Walter Mosley, Sara Paretsky, Robert B. Parker, and Mickey Spillane. Later, many hardboiled novels were published by houses specializing in paperback originals, most notably Gold Medal, and in later decades republished by houses such as Black Lizard.


title: Hardboiled

text: Hardboiled writing is also associated with "noir fiction". Eddie Duggan discusses the similarities and differences between the two related forms in his 1999 article on pulp writer Cornell Woolrich. In his full-length study of David Goodis, Jay Gertzman notes: "The best definition of hard boiled I know is that of critic Eddie Duggan. In noir, the primary focus is interior: psychic imbalance leading to self-hatred, aggression, sociopathy, or a compulsion to control those with whom one shares experiences. By contrast, hard boiled 'paints a backdrop of institutionalized social corruption.


title: Teleprinter

text: A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initially they were used in telegraphy, which developed in the late 1830s and 1840s as the first use of electrical engineering, though teleprinters were not used for telegraphy until 1887 at the earliest. The machines were adapted to provide a user interface to early mainframe computers and minicomputers, sending typed data to the computer and printing the response. Some models could also be used to create punched tape for data storage (either from typed input or from data received from a remote source) and to read back such tape for local printing or transmission.


title: Teleprinter

text: Teleprinters could use a variety of different communication media. These included a simple pair of wires; dedicated non-switched telephone circuits (leased lines); switched networks that operated similarly to the public telephone network (telex); and radio and microwave links (telex-on-radio, or TOR). A teleprinter attached to a modem could also communicate through standard switched public telephone lines. This latter configuration was often used to connect teleprinters to remote computers, particularly in time-sharing environments.


title: Teleprinter

text: Teleprinters have largely been replaced by fully electronic computer terminals which typically have a computer monitor instead of a printer (though the term "TTY" is still occasionally used to refer to them, such as in Unix systems). Teleprinters are still widely used in the aviation industry (see AFTN and airline teletype system), and variations called Telecommunications Devices for the Deaf (TDDs) are used by the hearing impaired for typed communications over ordinary telephone lines.


title: Teleprinter

text: The teleprinter evolved through a series of inventions by a number of engineers, including Samuel Morse, Alexander Bain, Royal Earl House, David Edward Hughes, Emile Baudot, Donald Murray, Charles L. Krum, Edward Kleinschmidt and Frederick G. Creed. Teleprinters were invented in order to send and receive messages without the need for operators trained in the use of Morse code. A system of two teleprinters, with one operator trained to use a keyboard, replaced two trained Morse code operators. The teleprinter system improved message speed and delivery time, making it possible for messages to be flashed across a country with little manual intervention.


title: Teleprinter

text: There were a number of parallel developments on both sides of the Atlantic Ocean. In 1835 Samuel Morse devised a recording telegraph, and Morse code was born. Morse's instrument used a current to displace the armature of an electromagnet, which moved a marker, therefore recording the breaks in the current. Cooke & Wheatstone received a British patent covering telegraphy in 1837 and a second one in 1840 which described a type-printing telegraph with steel type fixed at the tips of petals of a rotating brass daisy-wheel, struck by an “electric hammer” to print Roman letters through carbon paper onto a moving paper tape. In 1841 Alexander Bain devised an electromagnetic printing telegraph machine. It used pulses of electricity created by rotating a dial over contact points to release and stop a type-wheel turned by weight-driven clockwork; a second clockwork mechanism rotated a drum covered with a sheet of paper and moved it slowly upwards so that the type-wheel printed its signals in a spiral. The critical issue was to have the sending and receiving elements working synchronously. Bain attempted to achieve this using centrifugal governors to closely regulate the speed of the clockwork. It was patented, along with other devices, on April 21, 1841.


title: Teleprinter

text: By 1846, the Morse telegraph service was operational between Washington, D.C., and New York. Royal Earl House patented his printing telegraph that same year. He linked two 28-key piano-style keyboards by wire. Each piano key represented a letter of the alphabet and when pressed caused the corresponding letter to print at the receiving end. A "shift" key gave each main key two optional values. A 56-character typewheel at the sending end was synchronised to coincide with a similar wheel at the receiving end. If the key corresponding to a particular character was pressed at the home station, it actuated the typewheel at the distant station just as the same character moved into the printing position, in a way similar to the (much later) daisy wheel printer. It was thus an example of a synchronous data transmission system. House's equipment could transmit around 40 instantly readable words per minute, but was difficult to manufacture in bulk. The printer could copy and print out up to 2,000 words per hour. This invention was first put in operation and exhibited at the Mechanics Institute in New York in 1844.


title: Teleprinter

text: Landline teleprinter operations began in 1849, when a circuit was put in service between Philadelphia and New York City.


title: Teleprinter

text: In 1855, David Edward Hughes introduced an improved machine built on the work of Royal Earl House. In less than two years, a number of small telegraph companies, including Western Union in early stages of development, united to form one large corporation – Western Union Telegraph Co. – to carry on the business of telegraphy on the Hughes system.


title: Teleprinter

text: In France, Émile Baudot designed in 1874 a system using a five-unit code, which began to be used extensively in that country from 1877. The British Post Office adopted the Baudot system for use on a simplex circuit between London and Paris in 1897, and subsequently made considerable use of duplex Baudot systems on their Inland Telegraph Services.


title: Teleprinter

text: During 1901, Baudot's code was modified by Donald Murray (1865–1945, originally from New Zealand), prompted by his development of a typewriter-like keyboard. The Murray system employed an intermediate step, a keyboard perforator, which allowed an operator to punch a paper tape, and a tape transmitter for sending the message from the punched tape. At the receiving end of the line, a printing mechanism would print on a paper tape, and/or a reperforator could be used to make a perforated copy of the message. As there was no longer a direct correlation between the operator's hand movement and the bits transmitted, there was no concern about arranging the code to minimize operator fatigue, and instead Murray designed the code to minimize wear on the machinery, assigning the code combinations with the fewest punched holes to the most frequently used characters. The Murray code also introduced what became known as "format effectors" or "control characters" – the CR (Carriage Return) and LF (Line Feed) codes. A few of Baudot's codes moved to the positions where they have stayed ever since: the NULL or BLANK and the DEL code. NULL/BLANK was used as an idle code for when no messages were being sent.


title: Teleprinter

text: In the United States in 1902, electrical engineer Frank Pearne approached Joy Morton, head of Morton Salt, seeking a sponsor for research into the practicalities of developing a printing telegraph system. Joy Morton needed to determine whether this was worthwhile and so consulted mechanical engineer Charles L. Krum, who was vice president of the Western Cold Storage Company. Krum was interested in helping Pearne, so space was set up in a laboratory in the attic of Western Cold Storage. Frank Pearne lost interest in the project after a year and left to get involved in teaching. Krum was prepared to continue Pearne’s work, and in August, 1903 a patent was filed for a 'typebar page printer'. In 1904, Krum filed a patent for a 'type wheel printing telegraph machine' which was issued in August, 1907. In 1906 Charles Krum's son, Howard Krum, joined his father in this work. It was Howard who developed and patented the start-stop synchronizing method for code telegraph systems, which made possible the practical teleprinter.


title: Teleprinter

text: In 1908, a working teleprinter was produced by the Morkrum Company (formed between Joy Morton and Charles Krum), called the Morkrum Printing Telegraph, which was field tested with the Alton Railroad. In 1910, the Morkrum Company designed and installed the first commercial teletypewriter system on Postal Telegraph Company lines between Boston and New York City using the "Blue Code Version" of the Morkrum Printing Telegraph.


title: Teleprinter

text: In 1916, Edward Kleinschmidt filed a patent application for a typebar page printer. In 1919, shortly after the Morkrum company obtained their patent for a start-stop synchronizing method for code telegraph systems, which made possible the practical teleprinter, Kleinschmidt filed an application titled "Method of and Apparatus for Operating Printing Telegraphs" which included an improved start-stop method. The basic start-stop procedure, however, is much older than the Kleinschmidt and Morkrum inventions. It was already proposed by D'Arlincourt in 1870.


title: Teleprinter

text: Instead of wasting time and money in patent disputes on the start-stop method, Kleinschmidt and the Morkrum Company decided to merge and form the Morkrum-Kleinschmidt Company in 1924. The new company combined the best features of both their machines into a new typewheel printer for which Kleinschmidt, Howard Krum, and Sterling Morton jointly obtained a patent.


title: Teleprinter

text: In 1924 Britain's Creed & Company, founded by Frederick G. Creed, entered the teleprinter field with their Model 1P, a page printer, which was soon superseded by the improved Model 2P. In 1925 Creed acquired the patents for Donald Murray's Murray code, a rationalised Baudot code. The Model 3 tape printer, Creed’s first combined start-stop machine, was introduced in 1927 for the Post Office telegram service. This machine printed received messages directly on to gummed paper tape at a rate of 65 words per minute. Creed created his first keyboard perforator, which used compressed air to punch the holes. He also created a reperforator (receiving perforator) and a printer. The reperforator punched incoming Morse signals on to paper tape and the printer decoded this tape to produce alphanumeric characters on plain paper. This was the origin of the Creed High Speed Automatic Printing System, which could run at an unprecedented 200 words per minute. His system was adopted by the Daily Mail for daily transmission of the newspaper's contents. The Creed Model 7 page printing teleprinter was introduced in 1931 and was used for the inland Telex service. It worked at a speed of 50 baud, about 66 words a minute, using a code based on the Murray code.


title: Teleprinter

text: A teleprinter system was installed in the Bureau of Lighthouses, Airways Division, Flight Service Station Airway Radio Stations system in 1928, carrying administrative messages, flight information and weather reports. By 1938, the teleprinter network, handling weather traffic, extended over 20,000 miles, covering all 48 states except Maine, New Hampshire, and South Dakota.


title: Teleprinter

text: Most teleprinters used the 5-bit International Telegraph Alphabet No. 2 (ITA2). This limited the character set to 32 codes (2 = 32). One had to use a "FIGS" (for "figures") shift key to type numbers and special characters. Special versions of teleprinters had FIGS characters for specific applications, such as weather symbols for weather reports. Print quality was poor by modern standards. The ITA2 code was used asynchronously with start and stop bits: the asynchronous code design was intimately linked with the start-stop electro-mechanical design of teleprinters. (Early systems had used synchronous codes, but were hard to synchronize mechanically). Other codes, such as FIELDATA and Flexowriter, were introduced but never became as popular as ITA2.


title: Teleprinter

text: "Mark" and "space" are terms describing logic levels in teleprinter circuits. The native mode of communication for a teleprinter is a simple series DC circuit that is interrupted, much as a rotary dial interrupts a telephone signal. The marking condition is when the circuit is closed (current is flowing), the spacing condition is when the circuit is open (no current is flowing). The "idle" condition of the circuit is a continuous marking state, with the start of a character signalled by a "start bit", which is always a space. Following the start bit, the character is represented by a fixed number of bits, such as 5 bits in the ITA2 code, each either a mark or a space to denote the specific character or machine function. After the character's bits, the sending machine sends one or more stop bits. The stop bits are marking, so as to be distinct from the subsequent start bit. If the sender has nothing more to send, the line simply remains in the marking state (as if a continuing series of stop bits) until a later space denotes the start of the next character. The time between characters need not be an integral multiple of a bit time, but it must be at least the minimum number of stop bits required by the receiving machine.


title: Teleprinter

text: When the line is broken, the continuous spacing (open circuit, no current flowing) causes a receiving teleprinter to cycle continuously, even in the absence of stop bits. It prints nothing because the characters received are all zeros, the ITA2 blank (or ASCII) null character.


title: Teleprinter

text: Teleprinter circuits were generally leased from a communications common carrier and consisted of ordinary telephone cables that extended from the teleprinter located at the customer location to the common carrier central office. These teleprinter circuits were connected to switching equipment at the central office for Telex and TWX service. Private line teleprinter circuits were not directly connected to switching equipment. Instead, these private line circuits were connected to network hubs and repeaters configured to provide point to point or point to multipoint service. More than two teleprinters could be connected to the same wire circuit by means of a current loop.


title: Teleprinter

text: Earlier teleprinters had three rows of keys and only supported upper case letters. They used the 5 bit ITA2 code and generally worked at 60 to 100 words per minute. Later teleprinters, specifically the Teletype Model 33, used ASCII code, an innovation that came into widespread use in the 1960s as computers became more widely available.


title: Teleprinter

text: "Speed", intended to be roughly comparable to words per minute, is the standard term introduced by Western Union for a mechanical teleprinter data transmission rate using the 5-bit ITA2 code that was popular in the 1940s and for several decades thereafter. Such a machine would send 1 start bit, 5 data bits, and 1.42 stop bits. This unusual stop bit time is actually a rest period to allow the mechanical printing mechanism to synchronize in the event that a garbled signal is received. This is true especially on high frequency radio circuits where selective fading is present. Selective fading causes the mark signal amplitude to be randomly different from the space signal amplitude. Selective fading, or Rayleigh fading can cause two carriers to randomly and independently fade to different depths. Since modern computer equipment cannot easily generate 1.42 bits for the stop period, common practice is to either approximate this with 1.5 bits, or to send 2.0 bits while accepting 1.0 bits receiving.


title: Teleprinter

text: For example, a "60 speed" machine is geared at 45.5 baud (22.0 ms per bit), a "66 speed" machine is geared at 50.0 baud (20.0 ms per bit), a "75 speed" machine is geared at 56.9 baud (17.5 ms per bit), a "100 speed" machine is geared at 74.2 baud (13.5 ms per bit), and a "133 speed" machine is geared at 100.0 baud (10.0 ms per bit). 60 speed became the "de facto" standard for amateur radio RTTY operation because of the widespread availability of equipment at that speed and the U.S. Federal Communications Commission (FCC) restrictions to only 60 speed from 1953 to 1972. Telex, news agency wires and similar services commonly used 66 speed services. There was some migration to 75 and 100 speed as more reliable devices were introduced. However, the limitations of HF transmission such as excessive error rates due to multipath distortion and the nature of ionospheric propagation kept many users at 60 and 66 speed. Most audio recordings in existence today are of teleprinters operating at 60 words per minute, and mostly of the Teletype Model 15.


title: Teleprinter

text: Another measure of the speed of a teletypewriter was in total "operations per minute (OPM)". For example, 60 speed was usually 368 OPM, 66 speed was 404 OPM, 75 speed was 460 OPM, and 100 speed was 600 OPM. Western Union Telexes were usually set at 390 OPM, with 7.0 total bits instead of the customary 7.42 bits.


title: Teleprinter

text: Both wire-service and private teleprinters had bells to signal important incoming messages and could ring 24/7 while the power was turned on. For example, ringing 4 bells on UPI wire-service machines meant an "Urgent" message; 5 bells was a "Bulletin"; and 10 bells was a FLASH, used only for very important news, such as the assassination of John F. Kennedy.


title: Teleprinter

text: The teleprinter circuit was often linked to a 5-bit paper tape punch (or "reperforator") and reader, allowing messages received to be resent on another circuit. Complex military and commercial communications networks were built using this technology. Message centers had rows of teleprinters and large racks for paper tapes awaiting transmission. Skilled operators could read the priority code from the hole pattern and might even feed a "FLASH PRIORITY" tape into a reader while it was still coming out of the punch. Routine traffic often had to wait hours for relay. Many teleprinters had built-in paper tape readers and punches, allowing messages to be saved in machine-readable form and edited off-line.


title: Teleprinter

text: Communication by radio, known as "radioteletype" or "RTTY" (pronounced "ritty"), was also common, especially among military users. Ships, command posts (mobile, stationary, and even airborne) and logistics units took advantage of the ability of operators to send reliable and accurate information with a minimum of training. Amateur radio operators continue to use this mode of communication today, though most use computer-interface sound generators, rather than legacy hardware teleprinter equipment. Numerous modes are in use within the "ham radio" community, from the original ITA2 format to more modern, faster modes, which include error-checking of characters.


title: Teleprinter

text: A typewriter or electromechanical printer can print characters on paper, and execute operations such as move the carriage back to the left margin of the same line (carriage return), advance to the same column of the next line (line feed), and so on. Commands to control non-printing operations were transmitted in exactly the same way as printable characters by sending control characters with defined functions (e.g., the "line feed" character forced the carriage to move to the same position on the next line) to teleprinters. In modern computing and communications a few control characters, such as carriage return and line feed, have retained their original functions (although they are often implemented in software rather than activating electromechanical mechanisms to move a physical printer carriage) but many others are no longer required and are used for other purposes.


title: Teleprinter

text: Some teleprinters had a "Here is" key, which transmitted a fixed sequence of 20 or 22 characters, programmable by breaking tabs off a drum. This sequence could also be transmitted automatically upon receipt of an ENQ (control E) signal, if enabled. This was commonly used to identify a station; the operator could press the key to send the station identifier to the other end, or the remote station could trigger its transmission by sending the ENQ character, essentially asking "who are you?"


title: Teleprinter

text: The Gretag ETK-47 teleprinter developed in Switzerland by Edgar Gretener in 1947 uses a 14-bit start-stop transmission method similar to the 5-bit code used by other teleprinters. However, instead of a more-or-less arbitrary mapping between 5-bit codes and letters in the Latin alphabet, all characters (letters, digits, and punctuation) printed by the ETK are built from 14 basic elements on a print head, very similar to the 14 elements on a modern fourteen-segment display, each one selected independently by one of the 14 bits during transmission. Because it does not use a fixed character set, but instead builds up characters from smaller elements, the ETK printing element does not require modification to switch between Latin, Cyrillic, and Greek characters.


title: Teleprinter

text: In 1931, American inventor Edward Kleinschmidt formed Kleinschmidt Labs to pursue a different design of teleprinter. In 1944 Kleinschmidt demonstrated their lightweight unit to the Signal Corps and in 1949 their design was adopted for the Army's portable needs. In 1956, Kleinschmidt Labs merged with Smith-Corona, which then merged with the Marchant Calculating Machine Co., forming the SCM Corporation. By 1979, the Kleinschmidt division was turning to Electronic Data Interchange and away from mechanical products.


title: Teleprinter

text: Kleinschmidt machines, with the military as their primary customer, used standard military designations for their machines. The teleprinter was identified with designations such as a TT-4/FG, while communication "sets" to which a teleprinter might be a part generally used the standard Army/Navy designation system such as AN/FGC-25. This includes Kleinschmidt teleprinter TT-117/FG and tape reperforator TT-179/FG.


title: Teleprinter

text: Morkrum made their first commercial installation of a printing telegraph with the Postal Telegraph Company in Boston and New York in 1910. It became popular with railroads, and the Associated Press adopted it in 1914 for their wire service. Morkrum merged with their competitor Kleinschmidt Electric Company to become Morkrum-Kleinschmidt Corporation shortly before being renamed the Teletype Corporation.


title: Teleprinter

text: Italian office equipment maker Olivetti (est. 1908) started to manufacture teleprinters in order to provide Italian post offices with modern equipment to send and receive telegrams. The first models typed on a paper ribbon, which was then cut and glued into telegram forms.


title: Teleprinter

text: The Teletype Corporation, a part of American Telephone and Telegraph Company's Western Electric manufacturing arm since 1930, was founded in 1906 as the Morkrum Company. In 1925, a merger between Morkrum and Kleinschmidt Electric Company created the Morkrum-Kleinschmidt Company. The name was changed in December 1928 to Teletype Corporation. In 1930, Teletype Corporation was purchased by the American Telephone and Telegraph Company and became a subsidiary of Western Electric. In 1984, the divestiture of the Bell System resulted in the Teletype name and logo being replaced by the AT&T name and logo, eventually resulting in the brand being extinguished. The last vestiges of what had been the Teletype Corporation ceased in 1990, bringing to a close the dedicated teleprinter business. Despite its long-lasting trademark status, the word "Teletype" went into common generic usage in the news and telecommunications industries. Records of the United States Patent and Trademark Office indicate the trademark has expired and is considered dead.


title: Teleprinter

text: Teletype machines tended to be large, heavy, and extremely robust, capable of running non-stop for months at a time if properly lubricated. The Model 15 stands out as one of a few machines that remained in production for many years. It was introduced in 1930 and remained in production until 1963, a total of 33 years of continuous production. Very few complex machines can match that record. The production run was stretched somewhat by World War II—the Model 28 was scheduled to replace the Model 15 in the mid-1940s, but Teletype built so many factories to produce the Model 15 during World War II, it was more economical to continue mass production of the Model 15. The Model 15, in its receive only, no keyboard, version was the classic "news Teletype" for decades.


title: Teleprinter

text: Texas Instruments developed its own line of teletypes in 1971, the Silent 700. Their name came from the use of a thermal printer head to emit copy, making them substantially quieter than contemporary teletypes using impact printing, and some such as the 1975 Model 745 and 1983 Model 707 were even small enough to be sold as portable units. Certain models came with acoustic couplers and some had internal storage, initially cassette tape in the 1973 Models 732/733 ASR and later bubble memory in the 1977 Models 763/765, the first and one of the few commercial products to use the technology. In these units their storage capability essentially acted as a form of punched tape. The last Silent 700 was the 1987 700/1200 BPS, which was sold into the early 1990s.


title: Teleprinter

text: A global teleprinter network called "Telex" was developed in the late 1920s, and was used through most of the 20th century for business communications. The main difference from a standard teleprinter is that Telex includes a switched routing network, originally based on pulse-telephone dialing, which in the United States was provided by Western Union. AT&T developed a competing network called "TWX" which initially also used rotary dialing and Baudot code, carried to the customer premises as pulses of DC on a metallic copper pair. TWX later added a second ASCII-based service using Bell 103 type modems served over lines whose physical interface was identical to regular telephone lines. In many cases, the TWX service was provided by the same telephone central office that handled voice calls, using class of service to prevent POTS customers from connecting to TWX customers. Telex is still in use in some countries for certain applications such as shipping, news, weather reporting and military command. Many business applications have moved to the Internet as most countries have discontinued telex/TWX services.


title: Teleprinter

text: In addition to the 5-bit Baudot code and the much later seven-bit ASCII code, there was a six-bit code known as the Teletypesetter code (TTS) used by news wire services. It was first demonstrated in 1928 and began to see widespread use in the 1950s. Through the use of "shift in" and "shift out" codes, this six-bit code could represent a full set of upper and lower case characters, digits, symbols commonly used in newspapers, and typesetting instructions such as "flush left" or "center", and even "auxiliary font", to switch to italics or bold type, and back to roman ("upper rail").


title: Teleprinter

text: The TTS produces aligned text, taking into consideration character widths and column width, or line length.


title: Teleprinter

text: A Model 20 Teletype machine with a paper tape punch ("reperforator") was installed at subscriber newspaper sites. Originally these machines would simply punch paper tapes and these tapes could be read by a tape reader attached to a "Teletypesetter operating unit" installed on a Linotype machine. The "operating unit" was essentially a tape reader which actuated a mechanical box, which in turn operated the Linotype's keyboard and other controls, in response to the codes read from the tape, thus creating type for printing in newspapers and magazines.


title: Teleprinter

text: This allowed higher production rates for the Linotype, and was used both locally, where the tape was first punched and then fed to the machine, as well as remotely, using tape transmitters and receivers.


title: Teleprinter

text: Remote use played an essential role for distributing identical content, such as Syndicated columns, News agency news, Classified advertising, and more, to different publications across wide geographical areas.


title: Teleprinter

text: In later years the incoming 6-bit current loop signal carrying the TTS code was connected to a minicomputer or mainframe for storage, editing, and eventual feed to a phototypesetting machine.


title: Teleprinter

text: Computers used teleprinters for input and output from the early days of computing. Punched card readers and fast printers replaced teleprinters for most purposes, but teleprinters continued to be used as interactive time-sharing terminals until video displays became widely available in the late 1970s.


title: Teleprinter

text: Users typed commands after a prompt character was printed. Printing was unidirectional; if the user wanted to delete what had been typed, further characters were printed to indicate that previous text had been cancelled. When video displays first became available the user interface was initially exactly the same as for an electromechanical printer; expensive and scarce video terminals could be used interchangeably with teleprinters. This was the origin of the text terminal and the command-line interface.


title: Teleprinter

text: Paper tape was sometimes used to prepare input for the computer session off line and to capture computer output. The popular Teletype Model 33 used 7-bit ASCII code (with an eighth parity bit) instead of Baudot. The common modem communications settings, "Start/Stop Bits" and "Parity," stem from the Teletype era.


title: Teleprinter

text: In early operating systems such as Digital's RT-11, serial communication lines were often connected to teleprinters and were given device names starting with . This and similar conventions were adopted by many other operating systems. Unix and Unix-like operating systems use the prefix , for example , or (for pseudo-tty), such as , but some of them (e.g. Solaris & recent Linux) have replaced pty files by a pts folder (where "pt" stands for "pseudoterminal" instead). In many computing contexts, "TTY" has become the name for any text terminal, such as an external console device, a user dialing into the system on a modem on a serial port device, a printing or graphical computer terminal on a computer's serial port or the RS-232 port on a USB-to-RS-232 converter attached to a computer's USB port, or even a terminal emulator application in the window system using a pseudoterminal device.


title: Teleprinter

text: Teleprinters were also used to record fault printout and other information in some TXE telephone exchanges.


title: Teleprinter

text: Although printing news, messages, and other text at a distance is still universal, the dedicated teleprinter tied to a pair of leased copper wires was made functionally obsolete by the fax, personal computer, inkjet printer, email, and the Internet.


title: Teleprinter

text: In the 1980s, packet radio became the most common form of digital communications used in amateur radio. Soon, advanced multimode electronic interfaces such as the AEA PK-232 were developed, which could send and receive not only packet, but various other modulation types including Baudot. This made it possible for a home or laptop computer to replace teleprinters, saving money, complexity, space and the massive amount of paper which mechanical machines used.


title: Teleprinter

text: As a result, by the mid-1990s, amateur use of actual teleprinters had waned, though a core of "purists" still operate on equipment originally manufactured in the 1940s, 1950s, 1960s and 1970s.


title: Assassination attempts on Fidel Castro

text: The United States' Central Intelligence Agency made numerous unsuccessful attempts to assassinate Fidel Castro during his time as the president of Cuba.


title: Assassination attempts on Fidel Castro

text: Fidel Castro, whose primary goal was to create a communist state in Cuba, escaped numerous attempts on his life, not all to his knowledge. Castro went to Roman catholic boarding school, and began his political career while at the School of Law of the University of Havana. From here, his success caused chaos in the United States leading to the involvement of agencies such as the CIA. Following World War II, the United States became secretly engaged in a practice of international political assassinations and attempts on foreign leaders. For a considerable period of time, the U.S. Government officials vehemently denied any knowledge of this program since it would be against the United Nations Charter. On March 5, 1972, Richard Helms, Central Intelligence Agency (CIA) Director, declared that "no such activity or operations be undertaken, assisted, or suggested by any of our personnel." In 1975, the U.S. Senate convened the Senate Select Committee to Study Governmental Operations with Respect to Intelligence Activities chaired by the Senator Frank Church (D-Idaho). The Church Committee uncovered that CIA and other governmental agencies employed a tactic of plausible deniability during decision-making related to assassinations. CIA subordinates were deliberately shielding the higher-ranking officials from any responsibility by withholding the full amount of information about planned assassinations. Government employees were obtaining tacit approval of their acts by using euphemisms and sly wording in communications. Fidel Castro died in 2016, just ten years after passing the torch to his brother, Raul. He lived to the age of 90 despite the many attempts on his life that will be highlighted in this article.


title: Assassination attempts on Fidel Castro

text: According to CIA Director Richard Helms, Kennedy Administration officials exerted a heavy pressure on the CIA to "get rid of Castro." It explains a staggering number of assassination plots, aiming at creating a favorable impression on President John F. Kennedy. There were five phases in the assassination attempts, with planning involving the CIA, the Department of Defense, and the State Department: Prior to August 1960, from August 1960 to April 1961, from April 1961 to late 1961, from late 1961 to late 1962, and from late 1962 to late 1963. Fidel Castro survived over 600 assassination attempts, as well as attempts to end his political career in other ways. One of these attempts involved a chemical with comparable effects to the drug LSD sprayed in the air of the room where Castro would broadcast from his radio station, essentially to make him freak out, and speak incorrectly while on air. While this example may not be as dangerous as an assassination, if successful, this attempt would have been likely to ruin Castro's career. Another early attempt relied on the knowledge that he loved diving. The CIA decided to create an infected diving suit that would kill Castro slowly, over a long period of time, by lining the suit with tuberculosis. The infected diving suit did not succeed. The plan was betrayed and Castro learned of the attempt.


title: Assassination attempts on Fidel Castro

text: According to columnist Jack Anderson, the first CIA attempt to assassinate Castro was part of the Bay of Pigs Invasion operation, but five more CIA teams were sent, the last apprehended on a rooftop within rifle range of Castro, at the end of February or beginning of March 1963.


title: Assassination attempts on Fidel Castro

text: Attorney Robert Maheu, who was working as a CIA cutout at the time, was identified as the team leader, who recruited John Roselli, a gambler with contacts in the Italian American Mafia and Cuban underworlds. The CIA assigned two operations officers, William King Harvey and James O'Connell, to accompany Roselli to Miami to recruit the actual teams.


title: Assassination attempts on Fidel Castro

text: According to the CIA documents, the so-called Family Jewels that were declassified in 2007, one assassination attempt on Fidel Castro prior to the Bay of Pigs invasion involved noted American mobsters John Roselli, Sam Giancana and Santo Trafficante. At least some of the CIA assassination attempts on Castro were given the CIA project name ZRRIFLE.


title: Assassination attempts on Fidel Castro

text: In September 1960, Momo Salvatore Giancana, a successor of Al Capone's in the Chicago Outfit, and "Miami Syndicate" leader Santo Trafficante, who were both on the FBI's Ten Most Wanted list at that time, were indirectly contacted by the CIA about the possibility of Fidel Castro's assassination. Johnny Roselli, a member of the "Las Vegas Syndicate", was used to get access to Mafia bosses. The go-between from the CIA was Robert Maheu of the Howard Hughes organization, who introduced himself as a representative of several international businesses in Cuba that were expropriated by Castro. On September 14, 1960, Maheu met with Roselli in a New York City hotel and offered him US$150,000 for the "removal" of Castro. James O'Connell, who identified himself as Maheu's associate but who actually was the chief of the CIA's operational support division, was present during the meeting. The declassified documents did not reveal if Roselli, Giancana or Trafficante accepted a down payment for the job. According to the CIA files, it was Giancana who suggested poison pills as a means to doctor Castro's food or drinks. Such pills, manufactured by the CIA's Technical Services Division, were given to Giancana's nominee named Juan Orta. Giancana recommended Orta as being an official in the Cuban government, who had access to Castro.