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diff --git a/339/CH10/EX10.3/ex10_3.sce b/339/CH10/EX10.3/ex10_3.sce
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+Z0=50;
+//oscillation frequency
+f=2*10^9;
+w=2*%pi*f;
+//transistor S-parameters at oscillation frequency
+
+s_tr=[0.94*exp(%i*174/180*%pi),0.013*exp(-%i*98/180*%pi);1.9*exp(-%i*28/180*%pi),1.01*exp(-%i*17/180*%pi)];
+s11=ss2tf(1,1);
+s12=ss2tf(1,2);
+s21=ss2tf(2,1);
+s22=ss2tf(2,2);
+
+//find the Z-parameters of the transistor
+z_tr=ss2tf(s_tr,Z0);
+
+//attempt to add inductor to base in order to increase instability
+L=(0:0.01:2)*1e-9;
+
+Z_L=%i*w*L;
+z_L=[1,1;1,1];
+
+N=length(L);
+
+//create variables for the S_parameters of the transistor with the inductor
+s11=zeros([1 N]);
+s12=zeros([1 N]);
+s21=zeros([1 N]);
+s22=zeros([1 N]);
+
+//Rollett stability factor
+K=zeros([1 N]);
+
+for n=1:N
+   z_total=z_tr+z_L*Z_L(n);
+   s_total=ss2tf(z_total,Z0);
+   s11(n)=s_total(1,1);
+   s12(n)=s_total(1,2);
+   s21(n)=s_total(2,1);
+   s22(n)=s_total(2,2);
+   K(n)=(1-abs(s11(n))^2-abs(s22(n))^2+abs(det(s_total))^2)/2/abs(s12(n)*s21(n));
+end;
+
+plot(L/1e-9,K);
+title('Stability factor of the transistor in common-base mode vs. base inductance');
+xlabel('Base inductance L, nH');
+ylabel('Rollett stability factor \itk')