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38-537: S11 may refer to: Aircraft [ edit ] Fokker S-11 , a trainer aircraft Rans S-11 Pursuit , an American light aircraft SABCA S.11 , a Belgian prototype airliner Sikorsky S-11 , a Russian reconnaissance aircraft SPAD S.XI , a French reconnaissance biplane Rail and transit [ edit ] Lines [ edit ] S11 (Rhine-Ruhr S-Bahn) , Germany S11 (ZVV) , Zürich, Switzerland Line S11 (Milan suburban railway service) , Italy S11, of

76-415: A two-port network (a kind of four-terminal network or quadripole ) is an electrical network (i.e. a circuit) or device with two pairs of terminals to connect to external circuits. Two terminals constitute a port if the currents applied to them satisfy the essential requirement known as the port condition: the current entering one terminal must equal the current emerging from the other terminal on

114-580: A current amplifier is desired at the output. The resistors shown in the diagram can be general impedances instead. Off-diagonal h -parameters are dimensionless , while diagonal members have dimensions the reciprocal of one another. For reciprocal networks h 12 = – h 21 . For symmetrical networks h 11 h 22 – h 12 h 21 = 1 . For reciprocal lossless networks h 12 and h 21 are real, while h 11 and h 22 are purely imaginary. Note: Tabulated formulas in Table 2 make

152-434: A differential amplifier, I 1 ≈ − I 2 , making the output impedance of the mirror approximately compared to only r O without feedback (that is with R E = 0   Ω). At the same time, the impedance on the reference side of the mirror is approximately only a moderate value, but still larger than r E with no feedback. In the differential amplifier application, a large output resistance increases

190-669: A matrix of elements designated a 11 etc. as adopted by some authors and the inverse A'B'C'D' parameters as a matrix of elements designated b 11 etc. is used here for both brevity and to avoid confusion with circuit elements. The table below lists ABCD and inverse ABCD parameters for some simple network elements. The previous parameters are all defined in terms of voltages and currents at ports. S -parameters are different, and are defined in terms of incident and reflected waves at ports. S -parameters are used primarily at UHF and microwave frequencies where it becomes difficult to measure voltages and currents directly. On

228-509: A sports car Project S-11 , a video game September 11 attacks S11, a postcode district in Sheffield, England S-11, a creature in the Sharktopus film Voltage reflection coefficient S 11 {\displaystyle S_{11}} of a two-port network [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with

266-539: Is unilateral . The ABCD -parameters are known variously as chain, cascade, or transmission parameters. There are a number of definitions given for ABCD parameters, the most common is, Note: Some authors chose to reverse the indicated direction of I 2 and suppress the negative sign on I 2 . where For reciprocal networks AD – BC = 1 . For symmetrical networks A = D . For networks which are reciprocal and lossless, A and D are purely real while B and C are purely imaginary. This representation

304-661: Is a two seat piston-powered monoplane with maximum take of weight of 1100 kg (2425 lb) and a top speed of 209 km/h ( 130 mph, 113 kts). Also known as 'The Fokker Four Foundation', an organization of Dutch volunteers that operate a fleet of four Fokker S-11 'Instructor' aircraft, that are able to fly and are shown to the public, at various airshows around Europe. They are based at The Aviodrome museum at Lelystad Airport , Netherlands. Data from Jane's All The World's Aircraft 1953–54. General characteristics Performance Aircraft of comparable role, configuration, and era Two-port network In electronics ,

342-424: Is a two-port consisting of a L -network of resistors R 1 and R 2 . The z -parameters for this network are; Figure 11 shows two identical such networks connected in series-series. The total z -parameters predicted by matrix addition are; However, direct analysis of the combined circuit shows that, The discrepancy is explained by observing that R 1 of the lower two-port has been by-passed by

380-453: Is an outgrowth of reciprocity theorems first derived by Lorentz. In two-port mathematical models, the network is described by a 2 by 2 square matrix of complex numbers . The common models that are used are referred to as z - parameters , y - parameters , h - parameters , g - parameters , and ABCD - parameters , each described individually below. These are all limited to linear networks since an underlying assumption of their derivation

418-400: Is base resistance of transistor, r O is output resistance, and g m is mutual transconductance. The negative sign for g 12 reflects the convention that I 1 , I 2 are positive when directed into the two-port. A non-zero value for g 12 means the output current affects the input current, that is, this amplifier is bilateral . If g 12 = 0 , the amplifier

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456-399: Is preferred because when the parameters are used to represent a cascade of two-ports, the matrices are written in the same order that a network diagram would be drawn, that is, left to right. However, a variant definition is also in use, where The negative sign of – I 2 arises to make the output current of one cascaded stage (as it appears in the matrix) equal to the input current of

494-455: Is regarded as a " black box " with its properties specified by a matrix of numbers. This allows the response of the network to signals applied to the ports to be calculated easily, without solving for all the internal voltages and currents in the network. It also allows similar circuits or devices to be compared easily. For example, transistors are often regarded as two-ports, characterized by their h -parameters (see below) which are listed by

532-511: Is selected when a voltage amplifier is wanted at the output. Off-diagonal g-parameters are dimensionless, while diagonal members have dimensions the reciprocal of one another. The resistors shown in the diagram can be general impedances instead. Note: Tabulated formulas in Table 3 make the g -equivalent circuit of the transistor from Figure 8 agree with its small-signal low-frequency hybrid-pi model in Figure ;9. Notation: r π

570-449: Is shown for series-series connections in figures 11 and 12 below. When two-ports are connected in a series-series configuration as shown in figure 10, the best choice of two-port parameter is the z -parameters. The z -parameters of the combined network are found by matrix addition of the two individual z -parameter matrices. As mentioned above, there are some networks which will not yield directly to this analysis. A simple example

608-663: Is that T -parameters relate the waves at port 1 to the waves at port 2 whereas S -parameters relate the reflected waves to the incident waves. In this respect T -parameters fill the same role as ABCD parameters and allow the T -parameters of cascaded networks to be calculated by matrix multiplication of the component networks. T -parameters, like ABCD parameters, can also be called transmission parameters. The definition is, T -parameters are not as easy to measure directly as S -parameters. However, S -parameters are easily converted to T -parameters, see main article for details. When two or more two-port networks are connected,

646-511: Is that any given circuit condition is a linear superposition of various short-circuit and open circuit conditions. They are usually expressed in matrix notation, and they establish relations between the variables which are shown in figure 1. The difference between the various models lies in which of these variables are regarded as the independent variables . These current and voltage variables are most useful at low-to-moderate frequencies. At high frequencies (e.g., microwave frequencies),

684-431: The z mn are purely imaginary. Figure 3 shows a bipolar current mirror with emitter resistors to increase its output resistance. Transistor Q 1 is diode connected , which is to say its collector-base voltage is zero. Figure 4 shows the small-signal circuit equivalent to Figure 3. Transistor Q 1 is represented by its emitter resistance r E : a simplification made possible because

722-1380: The Hamburg S-Bahn , Germany S11, of the Karlsruhe Stadtbahn , Germany Locomotives [ edit ] ALCO S-11 , a diesel-electric switcher LSWR S11 class , a steam locomotive Sri Lanka Railways S11 , a diesel multiple unit Stations [ edit ] Kitanada Station , in Ōzu, Ehime Prefecture, Japan Morishita Station (Tokyo) , in Kōtō, Tokyo, Japan Myōhōji Station (Hyōgo) , in Suma-ku, Kobe, Hyōgo Prefecture, Japan Sakurayama Station , in Mizuho-ku, Nagoya, Aichi Prefecture, Japan Wutthakat BTS station , in Bangkok, Thailand Zenibako Station , in Otaru, Hokkaido, Japan Roads [ edit ] S11 highway (Georgia) Expressway S11 (Poland) County Route S11 (California) , United States Submarines [ edit ] Brazilian submarine Rio Grande do Sul (S11) ( Balao class) , in service 1963–1972 Brazilian submarine Rio Grande do Sul (S11) ( Tench class) , in service 1972–1978 HMS  Orpheus  (S11) , of

760-448: The h -equivalent circuit of the transistor from Figure 6 agree with its small-signal low-frequency hybrid-pi model in Figure 7. Notation: r π is base resistance of transistor, r O is output resistance, and g m is mutual transconductance. The negative sign for h 21 reflects the convention that I 1 , I 2 are positive when directed into the two-port. A non-zero value for h 12 means

798-849: The Royal Navy USS ; S-11  (SS-116) , of the United States Navy Other uses [ edit ] S11 (classification) , a disability swimming classification S11 (protest) , at the meeting of the World Economic Forum in Melbourne, Australia on September 11, 2000 40S ribosomal protein S11 British NVC community S11 , see swamps and tall-herb fens in the British National Vegetation Classification system Nissan Silvia (S11) ,

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836-527: The dependent current source in the hybrid-pi model for Q 1 draws the same current as a resistor 1 / g m connected across r π . The second transistor Q 2 is represented by its hybrid-pi model . Table 1 below shows the z-parameter expressions that make the z-equivalent circuit of Figure 2 electrically equivalent to the small-signal circuit of Figure 4. The negative feedback introduced by resistors R E can be seen in these parameters. For example, when used as an active load in

874-402: The difference-mode gain, a good thing, and a small mirror input resistance is desirable to avoid Miller effect . where All the Y -parameters have dimensions of siemens . For reciprocal networks y 12 = y 21 . For symmetrical networks y 11 = y 22 . For reciprocal lossless networks all the y mn are purely imaginary. where This circuit is often selected when

912-485: The first activities undertaken by Fokker after World War II was the design of a new military aircraft for elementary flying training, the S-11 Instructor. An aircraft trader already placed orders for 100 of these aircraft in 1946, before construction had even begun. The first prototype flew at Schiphol on 18 December 1947. During testing in early 1948 it was found that some aerodynamic changes had to be made to improve

950-631: The handling of the aircraft. Later that year demonstration flights for several air forces followed and eventually many S-11s were sold to the Royal Netherlands Air Force , Israeli Air Force , Italian Air Force , Brazilian Air Force , Paraguayan Air Force and Bolivian Air Force . Some 170 aircraft were license built in Italy as the Macchi M.416. A limited number of S-11 Instructors are still flying today. The Dutch Fokker Four foundation, dedicated to

988-425: The manufacturer. Any linear circuit with four terminals can be regarded as a two-port network provided that it does not contain an independent source and satisfies the port conditions. Examples of circuits analyzed as two-ports are filters , matching networks , transmission lines , transformers , and small-signal models for transistors (such as the hybrid-pi model ). The analysis of passive two-port networks

1026-458: The next. Without the minus sign the two currents would have opposite senses because the positive direction of current, by convention, is taken as the current entering the port. Consequently, the input voltage/current matrix vector can be directly replaced with the matrix equation of the preceding cascaded stage to form a combined A'B'C'D' matrix. The terminology of representing the ABCD parameters as

1064-1049: The other hand, incident and reflected power are easy to measure using directional couplers . The definition is, where the a k are the incident waves and the b k are the reflected waves at port k . It is conventional to define the a k and b k in terms of the square root of power. Consequently, there is a relationship with the wave voltages (see main article for details). For reciprocal networks S 12 = S 21 . For symmetrical networks S 11 = S 22 . For antimetrical networks S 11 = – S 22 . For lossless reciprocal networks | S 11 | = | S 22 | {\displaystyle |S_{11}|=|S_{22}|} and | S 11 | 2 + | S 12 | 2 = 1. {\displaystyle |S_{11}|^{2}+|S_{12}|^{2}=1.} Scattering transfer parameters, like scattering parameters, are defined in terms of incident and reflected waves. The difference

1102-535: The output voltage affects the input voltage, that is, this amplifier is bilateral . If h 12 = 0 , the amplifier is unilateral . The h -parameters were initially called series-parallel parameters . The term hybrid to describe these parameters was coined by D. A. Alsberg in 1953 in "Transistor metrology". In 1954 a joint committee of the IRE and the AIEE adopted the term h - parameters and recommended that these become

1140-437: The port condition being invalidated and the combination rule will no longer apply. A Brune test can be used to check the permissibility of the combination. This difficulty can be overcome by placing 1:1 ideal transformers on the outputs of the problem two-ports. This does not change the parameters of the two-ports, but does ensure that they will continue to meet the port condition when interconnected. An example of this problem

1178-677: The preservation of the aircraft, operates four S-11s and amongst other activities still performs with them on airshows . A version of the S-11 fitted with tricycle landing gear , the S-12 , was built by Fokker Industria Aeronautica in Brazil, and was used by the Brazilian Air Force as the T-22 Instructor . In Italy, 178 were produced under license by Macchi, and they were called M.416. The aircraft

S11 - Misplaced Pages Continue

1216-463: The same port. The ports constitute interfaces where the network connects to other networks, the points where signals are applied or outputs are taken. In a two-port network, often port 1 is considered the input port and port 2 is considered the output port. It is commonly used in mathematical circuit analysis . The two-port network model is used in mathematical circuit analysis techniques to isolate portions of larger circuits. A two-port network

1254-506: The same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=S11&oldid=1256110973 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Fokker S-11 One of

1292-433: The short-circuit between two terminals of the output ports. This results in no current flowing through one terminal in each of the input ports of the two individual networks. Consequently, the port condition is broken for both the input ports of the original networks since current is still able to flow into the other terminal. This problem can be resolved by inserting an ideal transformer in the output port of at least one of

1330-449: The standard method of testing and characterising transistors because they were "peculiarly adaptable to the physical characteristics of transistors". In 1956, the recommendation became an issued standard; 56 IRE 28.S2. Following the merge of these two organisations as the IEEE , the standard became Std 218-1956 and was reaffirmed in 1980, but has now been withdrawn. where Often this circuit

1368-425: The two-port networks. While this is a common text-book approach to presenting the theory of two-ports, the practicality of using transformers is a matter to be decided for each individual design. When two-ports are connected in a parallel-parallel configuration as shown in figure 13, the best choice of two-port parameter is the y -parameters. The y -parameters of the combined network are found by matrix addition of

1406-495: The two-port parameters of the combined network can be found by performing matrix algebra on the matrices of parameters for the component two-ports. The matrix operation can be made particularly simple with an appropriate choice of two-port parameters to match the form of connection of the two-ports. For instance, the z -parameters are best for series connected ports. The combination rules need to be applied with care. Some connections (when dissimilar potentials are joined) result in

1444-526: The use of power and energy variables is more appropriate, and the two-port current–voltage approach is replaced by an approach based upon scattering parameters . There are certain properties of two-ports that frequently occur in practical networks and can be used to greatly simplify the analysis. These include: where All the z -parameters have dimensions of ohms . For reciprocal networks z 12 = z 21 . For symmetrical networks z 11 = z 22 . For reciprocal lossless networks all

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