3-45TERMINATION IN A SHORT CIRCUITOn the line terminated in a short circuit, shown in figure 3-34, view D, the voltage is zero at the endDQG PD[LPXP DW IURP WKH HQG 7KH FXUUHQW LV PD[LPXP DW WKH HQG ]HUR DW IURP WKH HQG DQGDOWHUQDWHO\ PD[LPXP DQG ]HUR HYHU\ WKHUHDIWHU TERMINATION IN CAPACITANCEWhen a line is terminated in capacitance, the capacitor does not absorb energy, but returns all of theenergy to the circuit. This means there is 100 percent reflection. The current and voltage relationships aresomewhat more involved than in previous types of termination. For this explanation, assume that thecapacitive reactance is equal to the Z_{0} of the line. Current and voltage are in phase when they arrive at theend of the line, but in flowing through the capacitor and the characteristic impedance (Z_{0}) connected inseries, they shift in phase relationship. Current and voltage arrive in phase and leave out of phase. Thisresults in the standing-wave configuration shown in figure 3-34, view E. The standing wave of voltage isPLQLPXP DW D GLVWDQFH RI H[DFWO\ IURP WKH HQG ,I WKH FDSDFLWLYH UHDFWDQFH LV JUHDWHU WKDQ =_{0}(smallercapacitance), the termination looks more like an open circuit; the voltage minimum moves away from theend. If the capacitive reactance is smaller than Z_{0}, the minimum moves toward the end.TERMINATION IN INDUCTANCEWhen the line is terminated in an inductance, both the current and voltage shift in phase as theyarrive at the end of the line. When X_{L} is equal to Z_{0}, the resulting standing waves are as shown in figure3YLHZ ) 7KH FXUUHQW PLQLPXP LV ORFDWHG IURP WKH HQG RI WKH OLQH :KHQ WKH LQGXFWLYH UHDFWDQFHis increased, the standing waves appear closer to the end. When the inductive reactance is decreased, thestanding waves move away from the end of the line.TERMINATION IN A RESISTANCE NOT EQUAL TO THE CHARACTERISTIC IMPEDANCE(Z_{0})Whenever the termination is not equal to Z_{0}, reflections occur on the line. For example, if theterminating element contains resistance, it absorbs some energy, but if the resistive element does notequal the Z_{0} of the line, some of the energy is reflected. The amount of voltage reflected may be found byusing the equation:Where:E_{R} = the reflected voltageE_{i} = the incident voltageR_{R}= the terminating resistanceZ_{0}= the characteristic impedance of the lineIf you try different values of R_{L} in the preceding equation, you will find that the reflected voltage isequal to the incident voltage only when R_{L} equals 0 or is infinitely large. When R_{L }equals Z_{0}, no reflectedvoltage occurs. When R_{L }is greater than Z_{0}, E_{R} is positive, but less than E_{i}. As R_{L} increases and

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