Tektronix 1967SC free download

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ACTICAL A OACH VACU BE b y F. J. BECKETT Tektronix, Inc. Electronic Instrumentation Group Display Devices Development T\vo articles published in past issues of Service Scope contained information that, in our experience, is of particular benefit in analyzing circuits. The first article was "Simplifying Transistor Ihear-Amplifier Analysis" (issue #29, December, 1964). It describes a method for doing an adequate circuit analysis for trouble-sliooting or evaluation purposes on transistor circuits. I t employs the "Transresistance" concept rather than the complicatecl characteristic-family parameters. Thc second article was "Uiitlerstat~ding and Using Thevetiin's The- orem" (issue #40, October, 1966). I t offers a step-by-step explanation on how to apply the principles of The\-enin's Theorem to analyze and utidei-stand how a circuit operates. Now, in this issue of Ser\Gce Scope, \YC 131-ese~it first of three articles the that will offer a practical approach to transistor aiitl vacuum-tube amplifiers based on a simple D C analysis. These articles will, by virtue of additional in- formation and the tying together of some loose ends, combine and bring into better focus the concepts of "trai~s~esistaiice" and the priiiciples of Thevenin's Theorem. W e suggest that a "refresher" reading of the t\vo previous articles will enable our readers to more readily follo\v the inforination in this and the two following issues of Service Scope. The Editor L e t us consider the general equation for One is quite justified in looking at a current through a P.N. diode junction. OBJECTIVE transistor in terms of the two-diode con- V cept, refer to Figure 3. Therefore, assum- The objective of this paper is to present (1) ing diode A to be forward biased and di- a practical approach to Transistor and ode R to be reverse biased, as would be the where V = applied volts Vacuum-tube amplifiers based on a simple case if we were to operate the transistor