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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>There is nothing magic about a constant bias point, in fact it probably wants to vary with temperature for best linearity. At given temp the optimum bias point is defined as the point where the small signal Gm is half the large signal value. Thus when both transistors are conducting at low level the Gm is twice that of one device, and when only one is conducting for a large signalthe Gm is the same. So it is not worth obsessing over constancy. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>__________________<o:p></o:p></p><p class=MsoNormal>Clyde Washburn, K2UE<o:p></o:p></p><p class=MsoNormal><a href="mailto:k2ue@rochester.rr.com">k2ue@rochester.rr.com</a><o:p></o:p></p><p class=MsoNormal>82 Lasalle Pkwy<o:p></o:p></p><p class=MsoNormal>Victor, NY 14564-9610<o:p></o:p></p><p class=MsoNormal>585-317-7006<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>