a pe rm uoN V0 ruypN orEN Tu KY THUAr LopL! Ct nhan _2009 0 Thoi gian ldm bdi: 90 phrit. L Nguy6n tag hoat dQng cira mQt transistor lu0ng cpc pNp. II. cho so dd cria mQt m4ch dipn khuticrr aai aigi tric nrro t int ue, 1/ Tfnh fre sO khui5ch d4i rlign th6 6: lu,"l- ctra mach khui5ch aai aien tfre. - lu"*l 2/ Cho biiSt dang ciia rtudng d{c tuyi5n tAn s6 K : g(log t. Giai thich tpi sao h0 sO khui5ch dai diQn tfr6 f khdng nhu nhau eOi'vcri mqi tAn s6 f. 3l Mu6n mic h6i ti6p duong Ae tam tAng hQ sO ktrui5ch dai diQn th6 K, ph6l mic tu Aieri"Oi 2 cgc nio cfia transistor. III. Su bitin diQu bi€n dQ (AM): 1/ Nguy6n tic. 2l ve duong bi6u di6n cira s6ng cao tAn u(t) b!bi6n diQu bi€n <10 bdng tin hiQu u2(t) c6 dqng s6ng nhu hinh v€ duoi ttdy: H9 vi t6n SV: SO b6o danh:. {'tcth J 4}1Ll L{) "-dl J.nl,Vb*D'V . d4i rlign th6 6: lu,"l- ctra mach khui5ch aai aien tfre. - lu"*l 2/ Cho biiSt dang ciia rtudng d{c tuyi5n tAn s6 K : g(log t. Giai thich tpi sao h0 sO khui5ch dai. thich tpi sao h0 sO khui5ch dai diQn tfr6 f khdng nhu nhau eOi'vcri mqi tAn s6 f. 3l Mu6n mic h6i ti6p duong Ae tam tAng hQ sO ktrui5ch dai diQn th6 K, ph6l mic tu. s6ng nhu hinh v€ duoi ttdy: H9 vi t6n SV: SO b6o danh:. {'tcth J 4}1Ll L{) "-dl J.nl,Vb*D'V