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qr code vb.net library The BandPass DoubleTuned Transformer in .NET framework
The BandPass DoubleTuned Transformer Code 128 Code Set B Decoder In Visual Studio .NET Using Barcode Control SDK for .NET Control to generate, create, read, scan barcode image in Visual Studio .NET applications. USS Code 128 Creator In .NET Framework Using Barcode generator for VS .NET Control to generate, create Code128 image in Visual Studio .NET applications. THE TRANSMISSION OF INFORMATION THROUGH SPACE, that is, by wireless, is accomplished by impressing the information upon a carrier wave whose frequency is much higher than the highest frequency present in the information to be transmitted. The process of transferring information onto a highfrequency carrier wave is called modulation, and the carrier wave is said to be modulated by the information. An unmodulated carrier wave consists of a SINGLEFREQUENCY sinusoidal wave occupying just ONE POINT in the frequency spectrum. However, when a carrier wave is modulated new frequencies, above and below the carrier frequency, are created. These new frequencies are called sideband frequencies, and appear as a cluster of frequencies with the carrier frequency in the center.* It is for this reason that a circuit designed to handle a modulated carrier wave must be a BANDPASS type of network. One network that is useful in this regard is the doubletuned transformer, which let us now investigate with the aid of Fig. 232. Recognize Code 128 Code Set B In .NET Using Barcode scanner for .NET Control to read, scan read, scan image in VS .NET applications. Print Bar Code In .NET Framework Using Barcode printer for Visual Studio .NET Control to generate, create bar code image in .NET framework applications. Fig. 232
Bar Code Decoder In Visual Studio .NET Using Barcode reader for Visual Studio .NET Control to read, scan read, scan image in Visual Studio .NET applications. Code 128B Maker In C#.NET Using Barcode creator for .NET Control to generate, create Code 128 Code Set B image in Visual Studio .NET applications. To begin, the component labeled FET is a solidstate device called a elde ect transistor. The INPUT signal voltage is denoted by Vi , which we ll take as the reference " vector. The OUTPUT voltage is denoted by Vt ; thus the VOLTAGE GAIN of the stage is " " G Vt =Vi 393 Painting Code 128C In Visual Studio .NET Using Barcode creator for ASP.NET Control to generate, create Code 128 Code Set C image in ASP.NET applications. Code 128 Generation In VB.NET Using Barcode drawer for VS .NET Control to generate, create Code128 image in .NET applications. A elde ect transistor has very high internal gain but very high internal resistance, and is therefore a CONSTANTCURRENT type of generator (section 4.7). Thus the output current of a FET, for given Vi , remains very nearly constant as the value of the load Matrix Barcode Printer In VS .NET Using Barcode generation for .NET framework Control to generate, create Matrix Barcode image in Visual Studio .NET applications. Print Bar Code In .NET Framework Using Barcode encoder for VS .NET Control to generate, create bar code image in VS .NET applications. * See note 24 in Appendix, also note 25.
Bar Code Printer In Visual Studio .NET Using Barcode printer for .NET Control to generate, create barcode image in Visual Studio .NET applications. Encoding EAN8 In VS .NET Using Barcode creation for .NET framework Control to generate, create EAN8 image in .NET framework applications. CHAPTER 10 Magnetic Coupling. Transformers
Generating DataMatrix In VS .NET Using Barcode generation for ASP.NET Control to generate, create Data Matrix image in ASP.NET applications. Generating USS Code 39 In VS .NET Using Barcode printer for ASP.NET Control to generate, create Code 39 Full ASCII image in ASP.NET applications. impedance changes; this is true for all values of load impedances normally encountered in practical work. In Fig. 232 the constantcurrent output of the FET has the value gm Vi , where gm is a constant transistor parameter, called the transconductance, whose value depends upon the particular transistor being used. One way to begin the analysis of Fig. 232 is to convert the constantcurrent generator into an equivalent constantvoltage generator; one convenient way to do this is to start with Fig. 233. EAN13 Creator In None Using Barcode drawer for Online Control to generate, create GTIN  13 image in Online applications. DataMatrix Reader In C#.NET Using Barcode reader for Visual Studio .NET Control to read, scan read, scan image in Visual Studio .NET applications. Fig. 233
Painting ECC200 In ObjectiveC Using Barcode maker for iPad Control to generate, create Data Matrix image in iPad applications. Barcode Reader In Visual Basic .NET Using Barcode Control SDK for Visual Studio .NET Control to generate, create, read, scan barcode image in .NET framework applications. Fig. 234
Drawing Data Matrix ECC200 In C#.NET Using Barcode drawer for Visual Studio .NET Control to generate, create ECC200 image in Visual Studio .NET applications. 1D Barcode Printer In .NET Using Barcode generator for ASP.NET Control to generate, create 1D Barcode image in ASP.NET applications. In Fig. 233, note that we ve detached the constantcurrent generator and the capacitor of C farads from the primary side of Fig. 232. We now wish to convert Fig. 233 into an equivalent constantvoltage generator; this can be done by making use of Thevenin s theorem (section 4.6) as follows. First, in Fig. 233, note that the opencircuit voltage between terminals (a, b) is equal to the current gm Vi times the reactance of the capacitor C; thus the voltage of the equivalent generator is equal to jgm Vi XC , as shown in Fig. 234. Next, the internal impedance of the equivalent generator is equal to the impedance seen looking into terminals (a, b) in Fig. 233 with the FET replaced by its internal impedance. Since a FET has an extremely high internal resistance or impedance, it follows that the impedance, looking into terminals (a, b) in Fig. 233 is merely equal to the reactance of capacitor C, that is, jXC . Thus, by Thevenin s theorem, Fig. 234 is the constantvoltage equivalent of Fig. 233. Next let s consider the case of parallel R and L, as shown in Fig. 235. Fig. 235
Our object now is to convert the parallel circuit of Fig. 235 into an approximately equivalent series circuit. To do this, we begin by noting that the input impedance looking into terminals (a, b) in Fig. 235 is equal to (product of the two, over the sum) 2 jRXL jRXL R jXL RXL jR2 XL " Zp 2 2 R jXL R2 XL R2 XL
394 CHAPTER 10 Magnetic Coupling. Transformers
In the PARTICULAR APPLICATION HERE, however, the above equation can, for practical purposes, be considerably simpli ed. To do this, we must look back to Fig. 232 and note that L and C here constitute a PARALLEL resonant circuit with XL XC at the carrier frequency (the center frequency of the passband). As we found in section 8.7, the input impedance to a parallel circuit is high at and near the resonant frequency, even though the individual reactance values, XL and XC , will have quite low values at the same frequencies. At the same time, the value of the shunt resistance R must be much higher than either XL or XC , in order to prevent R from swamping out the e ect of the highimpedance parallel LC circuit at resonance, which would, among other things, cause the gain of the stage to be excessively low at and near the resonant frequency. 2 2 Thus, in practice, the value of R2 will be much greater than the value of either XL or XC , 2 and hence, for practical purposes, the denominator of eq. 394 can be written as R instead 2 of R2 XL ; thus eq. 394 becomes,

