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Jagdschloss Radar
Jagdschloss, officially the FuG 404, was the designation of a German early warning and battle control radar developed just prior to the start of World War II. Although it was built in limited numbers, Jadgschloss is historically important as the first radar system to feature a plan position indicator display, or "PPI". In Germany this type of display was referred to as "Panorama". It is named for Jagdschloss, a hunting lodge. Development The PPI effort started fairly early in the history of radar; Hans Hollmann filed a patent for the basic concept in 1936. At that time development of GEMA's other radars, notably the Freya, took priority, and work on the system did not start until 1939. By this time, radar development had progressed to the point were a prototype could be constructed by re-using systems from various production radars. A prototype system was built 35 km west of Berlin, known as the Tremmen Radar Tower. It mounted a large antenna consisting of two rows of four half-w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Warning Radar
An early-warning radar is any radar system used primarily for the long-range detection of its targets, i.e., allowing defences to be alerted as ''early'' as possible before the intruder reaches its target, giving the air defences the maximum time in which to operate. This contrasts with systems used primarily for tracking or gun laying, which tend to offer shorter ranges but offer much higher accuracy. EW radars tend to share a number of design features that improve their performance in the role. For instance, EW radar typically operates at lower frequencies, and thus longer wavelengths, than other types. This greatly reduces their interaction with rain and snow in the air, and therefore improves their performance in the long-range role where their coverage area will often include precipitation. This also has the side-effect of lowering their optical resolution, but this is not important in this role. Likewise, EW radars often use much lower pulse repetition frequency to maximi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telefunken
Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" appears in: * the product brand name "Telefunken"; * ''Gesellschaft für drahtlose Telegraphie m.b.H., System Telefunken'', founded 1903 in Berlin as a subsidiary of AEG and Siemens & Halske; * ''Telefunken, Gesellschaft für drahtlose Telegraphie m.b.H.'' (from 1923 to 1955 – since 1941 subsidiary of the AEG only); * ''Telefunken GmbH'' in 1955; * ''Telefunken Aktiengesellschaft (AG)'' in 1963; * Merger of AEG and Telefunken to form ''Allgemeine Elektrizitäts-Gesellschaft AEG-Telefunken'' (from 1967 to 1979); * AEG-TELEFUNKEN AG (from 1979 to 1985); * ''TELEFUNKEN Fernseh und Rundfunk GmbH'', Hanover (1972, subsidiary of AEG-TELEFUNKEN); * Telefunken electronic GmbH (a spin-off of AEG-Telefunken and DASA * the company (since 1992 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jagdschloss A Lehrgang
A ''Jagdschloss'' is a hunting lodge in German-speaking countries. It is a ''schloss'' set in a wildlife park or a hunting area (such as a forest, field or by a lake) that served primarily as accommodation for a ruler or aristocrat and his entourage while hunting in the area. Characteristics A ''Jagdschloss'' was often the venue for a banquet accompanying a hunt, and sometimes it also hosted festivals and other events. The term ''Jagdschloss'' is often equated to the ''Lustschloss'' or ''maison de plaisance'', particularly as the hunt was also a recreational activity. However, a ''Lustschloss'' and ''Jagdschloss'' differ in function as well as architecture. The layout and furnishing of a ''Lustschloss'' is unconstrained, while that of a ''Jagdschloss'' is always related to hunting: the walls may be adorned with antlers and other trophies, with scenes of hunting, and also by a deliberate use of wood or other natural materials. A ''Jagdschloss'' could also be very lavishly furnis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berlin Zoo
The Berlin Zoological Garden (german: link=no, Zoologischer Garten Berlin) is the oldest surviving and best-known zoo in Germany. Opened in 1844, it covers and is located in Berlin's Tiergarten. With about 1,380 different species and over 20,200 animals, the zoo presents one of the most comprehensive collections of species in the world. The zoo and its aquarium had more than 3.5 million visitors in 2017. It is the most-visited zoo in Europe and one of the most popular worldwide. Regular animal feedings are among its most famous attractions. Globally known animals like Knut, the polar bear, and Bao Bao, the giant panda have contributed to the zoo's public image. The zoo collaborates with many universities, research institutes, and other zoos around the world. It maintains and promotes European breeding programmes, helps safeguard several endangered species, and participates in several species reintroduction programs. History Opened on 1 August 1844, the Zoologischer Gart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoo Tower
The Zoo flak tower (German: ''Flakturm Tiergarten'', ''Tiergarten Flak Tower'' or commonly referred to as the "Zoo Tower") was a fortified flak tower that existed in Berlin from 1941 to 1947. It was one of several flak towers that protected Berlin from Allied bomber raids. Its primary role was as a gun platform to protect the government building district of Berlin; in addition, the '' Hochbunker'' (blockhouse) was designed to be used as a civilian air-raid shelter. It also contained a hospital and a radio transmitter for use by the German leadership, and provided secure storage facilities for art treasures. During the Battle of Berlin, it acted as a citadel and by depressing its large anti-aircraft artillery, its garrison was able to provide support for ground operations against the Soviet Red Army. Development The Berlin flak towers (''Flaktürme'', singular ''Flakturm'') were originally built as a response to an attack on Berlin by a relatively small force of British bom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flak
Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes surface based, subsurface ( submarine launched), and air-based weapon systems, associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defence. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. In some countries, such as Britain and Germany during the Second World War, the Soviet Union, and modern NATO and the United States, ground-based air defence and air defence aircraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone
A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from el, τῆλε (''tēle'', ''far'') and φωνή (''phōnē'', ''voice''), together meaning ''distant voice''. A common short form of the term is ''phone'', which came into use early in the telephone's history. In 1876, Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice at a second device. This instrument was further developed by many others, and became rapidly indispensable in business, government, and in households. The essential elements of a telephone are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaff (radar Countermeasure)
Chaff, originally called Window by the British and ''Düppel'' by the Second World War era German Luftwaffe (from the Berlin suburb where it was first developed), is a radar countermeasure in which aircraft or other targets spread a cloud of small, thin pieces of aluminium, metallized glass fibre or plastic, which either appears as a cluster of primary targets on radar screens or swamps the screen with multiple returns, in order to confuse and distract. Modern armed forces use chaff (in naval applications, for instance, using short-range SRBOC rockets) to distract radar-guided missiles from their targets. Most military aircraft and warships have chaff dispensing systems for self-defense. An intercontinental ballistic missile may release in its midcourse phase several independent warheads as well as penetration aids such as decoy balloons and chaff. Modern radar systems can distinguish chaff from target objects by measuring the Doppler shift; chaff quickly loses speed compared t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morse Code
Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one of the inventors of the telegraph. International Morse code encodes the 26 basic Latin letters through , one accented Latin letter (), the Arabic numerals, and a small set of punctuation and procedural signals ( prosigns). There is no distinction between upper and lower case letters. Each Morse code symbol is formed by a sequence of ''dits'' and ''dahs''. The ''dit'' duration is the basic unit of time measurement in Morse code transmission. The duration of a ''dah'' is three times the duration of a ''dit''. Each ''dit'' or ''dah'' within an encoded character is followed by a period of signal absence, called a ''space'', equal to the ''dit'' duration. The letters of a word are separated by a space of duration equal to three ''dits'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Identification Friend Or Foe
Identification, friend or foe (IFF) is an identification system designed for command and control. It uses a transponder that listens for an ''interrogation'' signal and then sends a ''response'' that identifies the broadcaster. IFF systems usually use radar frequencies, but other electromagnetic frequencies, radio or infrared, may be used. It enables military and civilian air traffic control interrogation systems to identify aircraft, vehicles or forces as friendly and to determine their bearing and range from the interrogator. IFF is used by both military and civilian aircraft. IFF was first developed during World War II, with the arrival of radar, and several friendly fire incidents. IFF can only positively identify friendly aircraft or other forces. If an IFF interrogation receives no reply or an invalid reply, the object is not positively identified as foe; friendly forces may not properly reply to IFF for various reasons such as equipment malfunction, and parties in the area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erstling IFF Transceiver
FuG 25a ''Erstling'' (German: ''"Firstborn"'', ''"Debut"'', sometimes FuGe) was an identification friend or foe (IFF) transponder installed in ''Luftwaffe'' aircraft starting in 1941 in order to allow German Freya radar stations to identify them as friendly. The system was also used as a navigation transponder as part of the EGON night bombing system during 1943 and 1944. It was the second IFF system to be used, replacing the FuG 25 ''Zwilling''. The basic concept of IFF had been introduced in November 1938 but little work was carried out on it initially. In 1939 the Würzburg radar was chosen to replace an earlier fire control radar from Lorenz. This led to the FuG 25 ''Zwilling'' which responded to the Würzburg signals. Meanwhile, the GEMA company introduced the long-range Freya radar and a more advanced IFF system to work with it. This Erstling unit was clearly superior to the Zwilling, but 10,000 Zwilling units had been produced and they were slow to abandon it. Starting i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parabolic Dish
A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated by a parabola revolving around its axis. The parabolic reflector transforms an incoming plane wave travelling along the axis into a spherical wave converging toward the focus. Conversely, a spherical wave generated by a point source placed in the focus is reflected into a plane wave propagating as a collimated beam along the axis. Parabolic reflectors are used to collect energy from a distant source (for example sound waves or incoming star light). Since the principles of reflection are reversible, parabolic reflectors can also be used to collimate radiation from an isotropic source into a parallel beam. In optics, parabolic mirrors are used to gather light in reflecting telescopes and solar furnaces, and project a beam of light in flashl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
