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+//Tested on Windows 7 Ultimate 32-bit
+//Chapter 6 Single Staje BJT Amplifiers Pg no. 195 and 196
+clear;
+clc;
+
+//Given Data
+//Figure 6.18,6.19,6.20
+
+VCC=15;//collector supply voltage in volts
+RC=5.6D3;//collector resistance in ohms
+RE0=390;//unbypassed emitter resistance in ohms
+RE1=390;//bypased emitter resistance in ohms
+R1=33D3;//divider network resistance R1 in ohms
+R2=4.7D3;//divider network resistance R2 in ohms
+VBE=0.7;//forward voltage drop of emitter diode in volts
+Bdc=140;//DC CE current gain beta
+Bac=160;//AC CE current gain beta
+VT=25D-3;//voltage equivalent of temperature in volts
+Vs=15D-3;//source rms voltage in volts
+Rs=600;//source internal impedance in ohms
+C1=10D-6;//input coupling capacitance in farads
+C2=50D-6;//emitter bypass capacitance in farads
+C3=10D-6;//output coupling capacitance in farads
+RL=[3.3D3 10D3 33D3 100D3 500D3 %inf] ;//load resistances in ohms
+
+
+//Solution
+
+for i=1:6
+
+printf("Case (%d)\n RL = %.1f kilo-ohms\n",i,RL(i)/1000);
+Rin_dc=Bdc*(RE0+RE1);//dc input resistance in ohms
+if 0.1*Rin_dc>R2 then
+    VB=VCC*R2/(R1+R2);//base to ground voltage in volts , since Rin>10*R2 it can be neglected
+end
+VE=VB-VBE;//emitter to ground voltage in volts
+IE=VE/(RE0+RE1);//emitter current in amperes
+IC=IE;//collector current is approximately equal to emitter current
+VC=VCC-IC*RC;//collector to ground voltage in volts
+re=VT/IE;//equivalent BJT model emitter resistance in ohms
+Rin_dash=Bac*(RE0+re);//internal resistance of BJT in ohms
+Rin=1/(1/R1+1/R2+1/Rin_dash);//total internal resistance is Rin=R1||R2||Rin'
+f=Rin/(Rs+Rin);//input attenuation factor
+if RL(i)==%inf then
+    RL_dash=RC;//effective load resistance
+else
+    RL_dash=1/(1/RC+1/RL(i));//effective load resistance
+end
+Gv=RL_dash/(re+RE0);//a.c. voltage gain
+Gv_dash=f*Gv;//overall a.c. voltage gain
+vc=Gv_dash*Vs;//a.c voltage at collector in volts
+
+printf("Output voltage vc = %.2f mV\n",vc*1000);
+end
+
+//error in answers in textbook due to approximations