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-rw-r--r--147/CH8/EX8.1/Example8_1.sce10
-rw-r--r--147/CH8/EX8.1/Result8_1.txt1
-rw-r--r--147/CH8/EX8.10/Example8_10.sce17
-rw-r--r--147/CH8/EX8.10/Result8_10.txt2
-rw-r--r--147/CH8/EX8.11/Example8_11.sce25
-rw-r--r--147/CH8/EX8.11/Result8_11.txt3
-rw-r--r--147/CH8/EX8.13/Example8_13.sce14
-rw-r--r--147/CH8/EX8.13/Result8_13.txt1
-rw-r--r--147/CH8/EX8.14/Example8_14.sce14
-rw-r--r--147/CH8/EX8.14/Result8_14.txt1
-rw-r--r--147/CH8/EX8.15/Example8_15.sce14
-rw-r--r--147/CH8/EX8.15/Result8_15.txt1
-rw-r--r--147/CH8/EX8.16/Example8_16.sce17
-rw-r--r--147/CH8/EX8.16/Result8_16.txt2
-rw-r--r--147/CH8/EX8.17/Example8_17.sce34
-rw-r--r--147/CH8/EX8.17/Result8_17.txt9
-rw-r--r--147/CH8/EX8.2/Example8_2.sce13
-rw-r--r--147/CH8/EX8.2/Result8_2.txt2
-rw-r--r--147/CH8/EX8.20/Example8_20.sce21
-rw-r--r--147/CH8/EX8.20/Result8_20.txt2
-rw-r--r--147/CH8/EX8.22/Example8_22.sce12
-rw-r--r--147/CH8/EX8.22/Result8_22.txt2
-rw-r--r--147/CH8/EX8.24/Example8_24.sce22
-rw-r--r--147/CH8/EX8.24/Result8_24.txt5
-rw-r--r--147/CH8/EX8.26/Example8_26.sce24
-rw-r--r--147/CH8/EX8.26/Result8_26.txt5
-rw-r--r--147/CH8/EX8.28/Example8_28.sce24
-rw-r--r--147/CH8/EX8.28/Result8_28.txt2
-rw-r--r--147/CH8/EX8.4/Example8_4.sce13
-rw-r--r--147/CH8/EX8.4/Result8_4.txt3
-rw-r--r--147/CH8/EX8.5/Example8_5.sce10
-rw-r--r--147/CH8/EX8.5/Result8_5.txt1
-rw-r--r--147/CH8/EX8.6/Example8_6.sce16
-rw-r--r--147/CH8/EX8.6/Result8_6.txt3
-rw-r--r--147/CH8/EX8.7/Example8_7.sce29
-rw-r--r--147/CH8/EX8.7/Result8_7.txt5
-rw-r--r--147/CH8/EX8.8/Example8_8.sce12
-rw-r--r--147/CH8/EX8.8/Result8_8.txt4
-rw-r--r--147/CH8/EX8.9/Example8_9.sce22
-rw-r--r--147/CH8/EX8.9/Result8_9.txt5
40 files changed, 422 insertions, 0 deletions
diff --git a/147/CH8/EX8.1/Example8_1.sce b/147/CH8/EX8.1/Example8_1.sce
new file mode 100644
index 000000000..f33a21df8
--- /dev/null
+++ b/147/CH8/EX8.1/Example8_1.sce
@@ -0,0 +1,10 @@
+close();
+clear;
+clc;
+//initial temperature 'T1', final temperature 'T2', leakage current doubles for 't' increase in temperature
+T1 = 25; //degree C
+T2 = 90; //degree C
+t = 6; //degree C
+Icbo1 = 500*10^(-9); //A
+Icbo2 = Icbo1*2^((T2-T1)/t); //A
+mprintf("Leakage current at %d degree C, Icbo2 = %0.2f uA",T2,Icbo2*10^6) \ No newline at end of file
diff --git a/147/CH8/EX8.1/Result8_1.txt b/147/CH8/EX8.1/Result8_1.txt
new file mode 100644
index 000000000..513e7208e
--- /dev/null
+++ b/147/CH8/EX8.1/Result8_1.txt
@@ -0,0 +1 @@
+Leakage current at 90 degree C, Icbo2 = 912.28 uA \ No newline at end of file
diff --git a/147/CH8/EX8.10/Example8_10.sce b/147/CH8/EX8.10/Example8_10.sce
new file mode 100644
index 000000000..89837a9be
--- /dev/null
+++ b/147/CH8/EX8.10/Example8_10.sce
@@ -0,0 +1,17 @@
+close();
+clear;
+clc;
+alpha = 0.99;
+Iceo = 0;
+Vee = 4;//V
+Vcc = 12;
+Vbeq = -0.7;
+Ieq = 1.1;//mA
+Vceq = -7;//V
+//By KVL around transistor terminals
+Re = (Vee+Vbeq)/Ieq;
+Vcbq = Vceq-Vbeq;
+Icq = alpha*Ieq;
+//By KVL around base-collector loop
+Rc = (Vcc+Vcbq)/Icq;
+mprintf('(a): Re = %0.0f ohm\n(b): Rc = %0.3f k ohm',Re,Rc);
diff --git a/147/CH8/EX8.10/Result8_10.txt b/147/CH8/EX8.10/Result8_10.txt
new file mode 100644
index 000000000..20e3b1fe7
--- /dev/null
+++ b/147/CH8/EX8.10/Result8_10.txt
@@ -0,0 +1,2 @@
+(a): Re = 3 ohm
+(b): Rc = 5.234 k ohm \ No newline at end of file
diff --git a/147/CH8/EX8.11/Example8_11.sce b/147/CH8/EX8.11/Example8_11.sce
new file mode 100644
index 000000000..03e207d29
--- /dev/null
+++ b/147/CH8/EX8.11/Example8_11.sce
@@ -0,0 +1,25 @@
+close();
+clear;
+clc;
+Rc = 300; //ohm
+Re = 200; //ohm
+R1 = 2000; //ohm
+R2 = 15000; //ohm
+Vbeq = 0.7; //V
+Vcc = 15; //V
+B = 110;
+Vcesat = 0;
+//(a)
+Rb = R1*R2/(R1+R2); //ohm
+Vbb = R1*Vcc/(R1+R2);
+Icq = (Vbb-Vbeq)/(Rb/(B+1) + Re); //A
+Ieq = Icq;
+//By KVL around collector circuit and using Icq = Ieq
+Vceq = Vcc-Icq*(Rc+Re); //V
+mprintf("(a) Maximum symmetrical swing in collective current = %0.2f mA\n\n",Icq*1000);
+//(b)
+Vcc = 10; //V
+Vbb = R1*Vcc/(R1+R2); //V
+Icq = (Vbb-Vbeq)/(Rb/(B+1) + Re); //A
+Vceq = Vcc - Icq*(Rc+Re);
+mprintf("(b) Maximum symmetrical swing in collective current in second case = %0.3f mA",Icq*1000);
diff --git a/147/CH8/EX8.11/Result8_11.txt b/147/CH8/EX8.11/Result8_11.txt
new file mode 100644
index 000000000..17394c0f6
--- /dev/null
+++ b/147/CH8/EX8.11/Result8_11.txt
@@ -0,0 +1,3 @@
+(a) Maximum symmetrical swing in collective current = 4.93 mA
+
+(b) Maximum symmetrical swing in collective current in second case = 2.207 mA \ No newline at end of file
diff --git a/147/CH8/EX8.13/Example8_13.sce b/147/CH8/EX8.13/Example8_13.sce
new file mode 100644
index 000000000..f005507cf
--- /dev/null
+++ b/147/CH8/EX8.13/Example8_13.sce
@@ -0,0 +1,14 @@
+close();
+clear;
+clc;
+Iceo = 0;
+Vcesat = 0;
+hfe = 100;
+Rc = 2000; //ohm
+Vcc = 12; //V
+Vbeq = 0.7; //V
+Vceq = Vcc/2;
+Ibq = (Vcc-Vceq)/((hfe+1)*Rc); //A
+//by KVL around transistor terminals
+Rf = (Vceq-Vbeq)/Ibq; //ohm
+mprintf("Rf for maximum symmetrical swing = %0.1f k ohm",Rf/1000); \ No newline at end of file
diff --git a/147/CH8/EX8.13/Result8_13.txt b/147/CH8/EX8.13/Result8_13.txt
new file mode 100644
index 000000000..87898060e
--- /dev/null
+++ b/147/CH8/EX8.13/Result8_13.txt
@@ -0,0 +1 @@
+Rf for maximum symmetrical swing = 178.4 k ohm \ No newline at end of file
diff --git a/147/CH8/EX8.14/Example8_14.sce b/147/CH8/EX8.14/Example8_14.sce
new file mode 100644
index 000000000..4b34afefa
--- /dev/null
+++ b/147/CH8/EX8.14/Example8_14.sce
@@ -0,0 +1,14 @@
+//Emiter voltage Vee, Collector Voltage Vcc, Resistance R
+close();
+clear;
+clc;
+Vee = 2;//V
+Vcc = 12;//V
+Rc = 2000;//ohm
+Vceq = -6.4;//V
+Vbeq = -0.3;
+Vcbq = Vceq - Vbeq;
+//From graph
+Ieq = 3*10^(-3);//A
+Re = (Vee+Vbeq)/Ieq;
+mprintf('Re = %0.1f ohm',Re); \ No newline at end of file
diff --git a/147/CH8/EX8.14/Result8_14.txt b/147/CH8/EX8.14/Result8_14.txt
new file mode 100644
index 000000000..7e37ab8ed
--- /dev/null
+++ b/147/CH8/EX8.14/Result8_14.txt
@@ -0,0 +1 @@
+Re = 566.7 ohm \ No newline at end of file
diff --git a/147/CH8/EX8.15/Example8_15.sce b/147/CH8/EX8.15/Example8_15.sce
new file mode 100644
index 000000000..0590a784d
--- /dev/null
+++ b/147/CH8/EX8.15/Example8_15.sce
@@ -0,0 +1,14 @@
+close();
+clear;
+clc;
+Ibq = 30*10^(-6); //A
+Re = 1000; //ohm
+Vcc = 15; //V
+Vcesat = 0.2; //V
+B = 80;
+a = B/(B+1);
+Icq = B*Ibq; //A
+Ieq = Icq/a; //A
+//KVL around collector circuit leads to minimum value of Rc
+Rc = (Vcc-Vcesat - Ieq*Re)/Icq; //ohm
+mprintf("Minimum value of Rc to maintain the transistor quiescent point at saturation, Rc = %0.3f k ohm",Rc/1000); \ No newline at end of file
diff --git a/147/CH8/EX8.15/Result8_15.txt b/147/CH8/EX8.15/Result8_15.txt
new file mode 100644
index 000000000..a9f012c7a
--- /dev/null
+++ b/147/CH8/EX8.15/Result8_15.txt
@@ -0,0 +1 @@
+Minimum value of Rc to maintain the transistor quiescent point at saturation, Rc = 5.154 k ohm \ No newline at end of file
diff --git a/147/CH8/EX8.16/Example8_16.sce b/147/CH8/EX8.16/Example8_16.sce
new file mode 100644
index 000000000..a00d413f5
--- /dev/null
+++ b/147/CH8/EX8.16/Example8_16.sce
@@ -0,0 +1,17 @@
+//Resistance R, Voltage V
+close();
+clear;
+clc;
+Re = 300;//ohm
+Rc = 500;//ohm
+Vcc = 15;//V
+Beta = 100;
+Vcesat = 0;
+Vbeq = 0.7;
+Rb = Beta*Re/10;
+//For maximum symmetrical swing
+Icq = 1/2*(Vcc/(Re+Rc));
+Vbb = Vbeq + Icq*Re*1.1;
+R1 = Rb/(1-(Vbb/Vcc));
+R2 = Rb*Vcc/Vbb;
+mprintf('R1 = %0.2f k ohm\nR2 = %0.2f k ohm',R1/1000,R2/1000); \ No newline at end of file
diff --git a/147/CH8/EX8.16/Result8_16.txt b/147/CH8/EX8.16/Result8_16.txt
new file mode 100644
index 000000000..286dceb72
--- /dev/null
+++ b/147/CH8/EX8.16/Result8_16.txt
@@ -0,0 +1,2 @@
+R1 = 4.02 k ohm
+R2 = 11.86 k ohm \ No newline at end of file
diff --git a/147/CH8/EX8.17/Example8_17.sce b/147/CH8/EX8.17/Example8_17.sce
new file mode 100644
index 000000000..80cbaf7ad
--- /dev/null
+++ b/147/CH8/EX8.17/Example8_17.sce
@@ -0,0 +1,34 @@
+close();
+clear;
+clc;
+Re = 200; //ohm
+R1 = 1000; //ohm
+R2 = 10*R1; //ohm
+Rc = 2000; //ohm
+Rl = Rc;
+Vbeq = 0.7; //V
+B = 100;
+Vcc = 15; //V
+//(a)
+Rb = (R1*R2)/(R1+R2); //ohm
+Vbb = R1*Vcc/(R1+R2); //V
+Icq = (Vbb-Vbeq)/(Rb/(B+1) + Re); //A
+mprintf("(a) Icq = %0.3f mA\n\n",Icq*1000);
+//(b)
+//KVL around collector circuit with Icq = Ieq
+Vceq = Vcc - Icq*(Re+Rc); //V
+mprintf("(b) Vceq = %0.2f V\n\n",Vceq);
+
+//(c)
+slope1 = 1/Rc + 1/Rl; //S
+Rac = 1/slope1;
+mprintf("(c) slope of ac load line, slope1 = %d mS\n\n",slope1*1000);
+
+//(d)
+slope2 = 1/(Rc+Re); //S
+Rdc = 1/slope2;
+mprintf("(d) slope of dc load line, slope2 = %0.3f mS\n\n",slope2*1000);
+Vcemax = Vceq + Icq*Rac;
+Ilm = (Vcemax-Vceq)/Rl; //A
+mprintf("(e) peak value of undistorted il, Ilm = %0.3f mA",Ilm*1000);
+
diff --git a/147/CH8/EX8.17/Result8_17.txt b/147/CH8/EX8.17/Result8_17.txt
new file mode 100644
index 000000000..0aff8bc50
--- /dev/null
+++ b/147/CH8/EX8.17/Result8_17.txt
@@ -0,0 +1,9 @@
+(a) Icq = 3.175 mA
+
+(b) Vceq = 8.01 V
+
+(c) slope of ac load line, slope1 = 1 mS
+
+(d) slope of dc load line, slope2 = 0.455 mS
+
+(e) peak value of undistorted il, Ilm = 1.588 mA \ No newline at end of file
diff --git a/147/CH8/EX8.2/Example8_2.sce b/147/CH8/EX8.2/Example8_2.sce
new file mode 100644
index 000000000..c08d06eba
--- /dev/null
+++ b/147/CH8/EX8.2/Example8_2.sce
@@ -0,0 +1,13 @@
+//Base to base collector leakage current Icbo
+close();
+clear;
+clc;
+Beta = 100;
+Icbo = 5*10^(-6);
+//Part(a)
+Ib = 0;
+Iceo = (Beta+1)*Icbo;
+//Part(b)
+Ib = 40*10^(-6);
+Ic = Beta*Ib + (Beta+1)*Icbo;
+mprintf('(a):Iceo = %0.0f micro A \n(b):Ic = %0.3f mA',Iceo*10^(6),Ic*1000); \ No newline at end of file
diff --git a/147/CH8/EX8.2/Result8_2.txt b/147/CH8/EX8.2/Result8_2.txt
new file mode 100644
index 000000000..7b9b84f5f
--- /dev/null
+++ b/147/CH8/EX8.2/Result8_2.txt
@@ -0,0 +1,2 @@
+(a):Iceo = 505 micro A
+(b):Ic = 4.505 mA \ No newline at end of file
diff --git a/147/CH8/EX8.20/Example8_20.sce b/147/CH8/EX8.20/Example8_20.sce
new file mode 100644
index 000000000..f155fbe17
--- /dev/null
+++ b/147/CH8/EX8.20/Example8_20.sce
@@ -0,0 +1,21 @@
+//input resistance hie, reverse voltage ratio hre
+//forward current gain hfe, output admittance hoe
+close();
+clear;
+clc;
+Rc = 800;//ohm
+Rl = Rc;
+Ri = 0;
+R1 = 1200;//ohm
+R2 = 2700;
+hre = 0;
+hoe = 100*10^(-6);//s
+hfe = 90;
+hie = 200;
+Rb = R1*R2/(R1+R2);
+syms ib;
+il = -(Rc/hoe)/(Rc/hoe+Rl/hoe+Rl*Rc)*hfe*ib;
+Av = dbl(Rl*il/(hie*ib));
+//Current gain 'Ai'
+Ai = dbl(Rb/(Rb+hie)*il/ib);
+mprintf('Voltage gain Av = %0.2f\nCurrent gain Ai = %0.2f',Av,Ai); \ No newline at end of file
diff --git a/147/CH8/EX8.20/Result8_20.txt b/147/CH8/EX8.20/Result8_20.txt
new file mode 100644
index 000000000..610fc4b6a
--- /dev/null
+++ b/147/CH8/EX8.20/Result8_20.txt
@@ -0,0 +1,2 @@
+Voltage gain Av = -173.08
+Current gain Ai = -34.87 \ No newline at end of file
diff --git a/147/CH8/EX8.22/Example8_22.sce b/147/CH8/EX8.22/Example8_22.sce
new file mode 100644
index 000000000..be0097ff4
--- /dev/null
+++ b/147/CH8/EX8.22/Example8_22.sce
@@ -0,0 +1,12 @@
+close();
+clear;
+clc;
+//For hfb, at Vcbq = 6.1 V
+dic = 3.97-2.0;
+die = 4-2;
+hfb = dic/die;
+//For hob at Ieq = 3 mA
+dic = 3.05-2.95;
+dveb = -10-(-2);
+hob = dic/dveb;
+mprintf('hfb = %0.3f\nhob = %0.1f micro S',hfb,hob*10^(3)); \ No newline at end of file
diff --git a/147/CH8/EX8.22/Result8_22.txt b/147/CH8/EX8.22/Result8_22.txt
new file mode 100644
index 000000000..baa6f0e02
--- /dev/null
+++ b/147/CH8/EX8.22/Result8_22.txt
@@ -0,0 +1,2 @@
+hfb = 0.985
+hob = -12.5 micro S \ No newline at end of file
diff --git a/147/CH8/EX8.24/Example8_24.sce b/147/CH8/EX8.24/Example8_24.sce
new file mode 100644
index 000000000..194fa01ec
--- /dev/null
+++ b/147/CH8/EX8.24/Example8_24.sce
@@ -0,0 +1,22 @@
+//input resistance hie, reverse voltage ratio hre
+//forward current gain hfe, output admittance hoe
+close();
+clear;
+clc;
+hie = 1500;
+hfe = 40;
+hre = 0;
+hoe = 30;
+Ri = 1000;//ohm
+Rc2 = 20000;
+Rc1 = 10000;
+Rb1 = 5000;
+Rb2 = 5000;
+Av2 = -hfe*Rc2/(hie*(1+hoe*10^(-6)*Rc2));
+Zin2 = Rb2*hie/(Rb2+hie);
+Av1 = -hfe*Zin2*Rc1/(hie*(Rc1+Zin2+hoe*Zin2*Rc1*10^(-6)));
+Zin1 = Rb1*hie/(Rb1+hie);
+//vin/vi = vin_i
+vin_i = Zin1/(Zin1+Ri);
+Av = vin_i*Av1*Av2
+mprintf('Final stage voltage gain Av2 = %0.1f\nFinal stage input impedance Zin2 = %0.3f k ohm \nInitial staage voltage gain Av1 = %0.1f\nAmplifier input impedance Zin1 = %0.3f k ohm\nAmplifier voltage gain = %0.0f',Av2,Zin2/1000,Av1,Zin1/1000,Av); \ No newline at end of file
diff --git a/147/CH8/EX8.24/Result8_24.txt b/147/CH8/EX8.24/Result8_24.txt
new file mode 100644
index 000000000..9e36cb1cc
--- /dev/null
+++ b/147/CH8/EX8.24/Result8_24.txt
@@ -0,0 +1,5 @@
+Final stage voltage gain Av2 = -333.3
+Final stage input impedance Zin2 = 1.154 k ohm
+Initial staage voltage gain Av1 = -26.8
+Amplifier input impedance Zin1 = 1.154 k ohm
+Amplifier voltage gain = 4778 \ No newline at end of file
diff --git a/147/CH8/EX8.26/Example8_26.sce b/147/CH8/EX8.26/Example8_26.sce
new file mode 100644
index 000000000..c4a1333fe
--- /dev/null
+++ b/147/CH8/EX8.26/Example8_26.sce
@@ -0,0 +1,24 @@
+close();
+clear;
+clc;
+Vcc = 24;//V
+Rc = 5000;//ohm
+Re = 200;
+Vcesat = 0;
+Icbo = 0;
+//Maximum amplitude 'Icq'
+Icq = 1/2*(Vcc/(Rc+Re));
+Icm1 = 0;
+Icm2 = Icq*50/100;
+Icm3 = Icq;
+Ps = Vcc*Icq;
+Po1 = Icm1^2*Rc/2;
+Po2 = Icm2^2*Rc/2;
+Po3 = Icm3^2*Rc/2;
+Pc1 = Icq^2*(Rc+Re)-Po1;
+Pc2 = Icq^2*(Rc+Re)-Po2;
+Pc3 = Icq^2*(Rc+Re)-Po3;
+n1 = Po1/Ps*100;
+n2 = Po2/Ps*100;
+n3 = Po3/Ps*100;
+mprintf('(a): Icq = %0.3f mA\n(b): Ps = %0.2f mW\n(c):Values of Po at 0,50%% and 100%% of maximum undistorted collector current are %0.0f , %0.2f and %0.2f mW respectively.\n(d): Values of Pc are %0.1f, %0.2f and %0.2f mW\n(e): Values of efficiency are %0.0f, %0.2f %% and %0.2f %%',Icq*1000,Ps*1000,Po1*1000,Po2*1000,Po3*1000,Pc1*1000,Pc2*1000,Pc3*1000,n1,n2,n3); \ No newline at end of file
diff --git a/147/CH8/EX8.26/Result8_26.txt b/147/CH8/EX8.26/Result8_26.txt
new file mode 100644
index 000000000..c8a20e45b
--- /dev/null
+++ b/147/CH8/EX8.26/Result8_26.txt
@@ -0,0 +1,5 @@
+(a): Icq = 2.308 mA
+(b): Ps = 55.38 mW
+(c):Values of Po at 0,50% and 100% of maximum undistorted collector current are 0 , 3.33 and 13.31 mW respectively.
+(d): Values of Pc are 27.7, 24.36 and 14.38 mW
+(e): Values of efficiency are 0, 6.01 % and 24.04 % \ No newline at end of file
diff --git a/147/CH8/EX8.28/Example8_28.sce b/147/CH8/EX8.28/Example8_28.sce
new file mode 100644
index 000000000..d4d0b68a6
--- /dev/null
+++ b/147/CH8/EX8.28/Example8_28.sce
@@ -0,0 +1,24 @@
+close();
+clear;
+clc;
+Vbe = 0.7;
+alpha = 0.99;
+Icbo = 0;
+Vb = 1;//V
+Re = 100;
+Rc = 1000;
+Vcc = 10;
+Icbo = 0;
+Beta = alpha/(1-alpha);
+//Part (i)
+Rb = 1000;
+Ic = Beta*(Vb-Vbe)/(Rb+(1+Beta)*Re)+(Rb+Re)/(Rb+(1+Beta)*Re)*(1+Beta)*Icbo;
+//Quiescent value of Vce is
+Vce1 = Vcc - Ic*(Rc+Re);
+//Part (ii)
+Rb = 10000;
+Ic = Beta*(Vb-Vbe)/(Rb+(1+Beta)*Re)+(Rb+Re)/(Rb+(1+Beta)*Re)*(1+Beta)*Icbo;
+//Quiescent value of Vce is
+Vce2 = Vcc - Ic*(Rc+Re);
+mprintf('(i)Quiescent value of Vce = %0.2f V\n(ii)Quiescent value of Vce = %0.4f V',Vce1,Vce2);
+ \ No newline at end of file
diff --git a/147/CH8/EX8.28/Result8_28.txt b/147/CH8/EX8.28/Result8_28.txt
new file mode 100644
index 000000000..91a5d908c
--- /dev/null
+++ b/147/CH8/EX8.28/Result8_28.txt
@@ -0,0 +1,2 @@
+(i)Quiescent value of Vce = 7.03 V
+(ii)Quiescent value of Vce = 8.3665 V \ No newline at end of file
diff --git a/147/CH8/EX8.4/Example8_4.sce b/147/CH8/EX8.4/Example8_4.sce
new file mode 100644
index 000000000..ac2cf2202
--- /dev/null
+++ b/147/CH8/EX8.4/Example8_4.sce
@@ -0,0 +1,13 @@
+//Base current Ibq
+close();
+clear;
+clc;
+alpha = 0.98;
+Ibq = 30*10^(-6);//A
+Beta = alpha/(1-alpha);
+Icq = Beta*Ibq;
+Ieq = Icq/alpha;
+mprintf('Beta = %0.0f\nIcq = %0.2f mA\nIeq = %0.2f mA',Beta,Icq*1000,Ieq*1000);
+
+
+
diff --git a/147/CH8/EX8.4/Result8_4.txt b/147/CH8/EX8.4/Result8_4.txt
new file mode 100644
index 000000000..5ee73a93b
--- /dev/null
+++ b/147/CH8/EX8.4/Result8_4.txt
@@ -0,0 +1,3 @@
+Beta = 49
+Icq = 1.47 mA
+Ieq = 1.50 mA \ No newline at end of file
diff --git a/147/CH8/EX8.5/Example8_5.sce b/147/CH8/EX8.5/Example8_5.sce
new file mode 100644
index 000000000..1b1697072
--- /dev/null
+++ b/147/CH8/EX8.5/Example8_5.sce
@@ -0,0 +1,10 @@
+close();
+clear;
+clc;
+Ibq = 40*10^(-6); //A
+Vbb = 6; //V
+Vbeq = 0.7; //for Si transistor
+//By KVL around the base-emitter
+//Vbb = Ibq*Rb + Vbeq;
+Rb = (Vbb-Vbeq)/Ibq; //ohm
+mprintf("Rb = %0.1f k ohm",Rb/1000); \ No newline at end of file
diff --git a/147/CH8/EX8.5/Result8_5.txt b/147/CH8/EX8.5/Result8_5.txt
new file mode 100644
index 000000000..62e62257b
--- /dev/null
+++ b/147/CH8/EX8.5/Result8_5.txt
@@ -0,0 +1 @@
+Rb = 132.5 k ohm \ No newline at end of file
diff --git a/147/CH8/EX8.6/Example8_6.sce b/147/CH8/EX8.6/Example8_6.sce
new file mode 100644
index 000000000..e147d21de
--- /dev/null
+++ b/147/CH8/EX8.6/Example8_6.sce
@@ -0,0 +1,16 @@
+close();
+clear;
+clc;
+Beta = 100;
+Ibq = 20*10^(-6);
+Vcc = 15;//V
+Rc = 3000;//ohm
+Icbo = 0;
+alpha = Beta/(Beta+1);
+Icq = Beta*Ibq;
+Ieq = Icq/alpha;
+Vceq = Vcc-Icq*Rc;
+//Part (c)
+Rc = 6000;
+Vceq_c = Vcc-Icq*Rc;
+mprintf('(a):Ieq = %0.2f mA\n(b):Vceq = %0.0f V\n(c):Vceq = %0.0f V',Ieq*1000,Vceq,Vceq_c); \ No newline at end of file
diff --git a/147/CH8/EX8.6/Result8_6.txt b/147/CH8/EX8.6/Result8_6.txt
new file mode 100644
index 000000000..bdcf7ffcd
--- /dev/null
+++ b/147/CH8/EX8.6/Result8_6.txt
@@ -0,0 +1,3 @@
+(a):Ieq = 2.02 mA
+(b):Vceq = 9 V
+(c):Vceq = 3 V \ No newline at end of file
diff --git a/147/CH8/EX8.7/Example8_7.sce b/147/CH8/EX8.7/Example8_7.sce
new file mode 100644
index 000000000..ec1f1c87d
--- /dev/null
+++ b/147/CH8/EX8.7/Example8_7.sce
@@ -0,0 +1,29 @@
+close();
+clear;
+clc;
+Ibq = 40*10^(-6); //A
+Icbo = 0;
+Vbb = 6; //V
+Re = 1000; //ohm
+B = 80;
+Iceo = 0;
+Vcc = 15; //V
+Rc = 3000; //ohm
+Vbeq = 0.7; //for Si transistor
+
+//(a)
+a = B/(B+1);
+Ieq = Ibq/(1-a); //A
+mprintf("(a) Ieq = %0.3f mA\n\n",Ieq*1000);
+
+//(b)
+//Applying KVL around the base-emitter loop gives
+//Vbb = Ibq*Rb + Vbeq + Ieq*Re;
+Rb = (Vbb-Vbeq-Ieq*Re)/Ibq; //ohm
+mprintf("(b) Rb = %0.2f k ohm\n\n",Rb/1000);
+
+//(c)
+Icq = B*Ibq; //A
+//By KVL around collector circuit
+Vceq = Vcc-Ieq*Re-Icq*Rc;
+mprintf("(c) Vceq = %0.2f V\n\n",Vceq); \ No newline at end of file
diff --git a/147/CH8/EX8.7/Result8_7.txt b/147/CH8/EX8.7/Result8_7.txt
new file mode 100644
index 000000000..1a0b439a6
--- /dev/null
+++ b/147/CH8/EX8.7/Result8_7.txt
@@ -0,0 +1,5 @@
+(a) Ieq = 3.240 mA
+
+(b) Rb = 51.50 k ohm
+
+(c) Vceq = 2.16 V
diff --git a/147/CH8/EX8.8/Example8_8.sce b/147/CH8/EX8.8/Example8_8.sce
new file mode 100644
index 000000000..03296324d
--- /dev/null
+++ b/147/CH8/EX8.8/Example8_8.sce
@@ -0,0 +1,12 @@
+close();
+clear;
+clc;
+Ibq = 30*10^(-6);//A
+Vceq = 8;//V
+Vcc = 14;//V
+//From graph
+Icq = 2.7*10^(-3);//A
+Rc = Vcc/(6.25*10^(-3));
+Ieq = Icq+Ibq;
+Beta = Icq/Ibq;
+mprintf('Icq = %0.1f mA\nRc = %0.2f k ohm\nIeq = %0.2f mA\nBeta = %0.0f',Icq*1000,Rc/1000,Ieq*1000,Beta); \ No newline at end of file
diff --git a/147/CH8/EX8.8/Result8_8.txt b/147/CH8/EX8.8/Result8_8.txt
new file mode 100644
index 000000000..f8ce3717c
--- /dev/null
+++ b/147/CH8/EX8.8/Result8_8.txt
@@ -0,0 +1,4 @@
+Icq = 2.7 mA
+Rc = 2.24 k ohm
+Ieq = 2.73 mA
+Beta = 90 \ No newline at end of file
diff --git a/147/CH8/EX8.9/Example8_9.sce b/147/CH8/EX8.9/Example8_9.sce
new file mode 100644
index 000000000..fb3ac6429
--- /dev/null
+++ b/147/CH8/EX8.9/Example8_9.sce
@@ -0,0 +1,22 @@
+close();
+clear;
+clc;
+B = 80;
+Vceq = 8; //V
+Rc = 3000; //ohm
+Vcc = 15; //V
+Vbeq = 0.7; //for Si transistor
+
+//(a) by KVL around collector circuit
+Icq = (Vcc-Vceq)/Rc; //A
+mprintf("(a) Icq = %0.3f mA\n\n",Icq*1000);
+
+//(b)if leakage current is neglected
+Ibq = Icq/B; //A
+Rb = (Vcc-Vbeq)/Ibq; //ohm
+mprintf("(b) Rb for Si device = %0.1f k ohm\n\n",Rb/1000);
+
+//(c)
+Vbeq = 0.3; //for Ge transisor
+Rb = (Vcc-Vbeq)/Ibq;
+mprintf("(c) Rb for Ge device = %0.1f k ohm",Rb/1000);
diff --git a/147/CH8/EX8.9/Result8_9.txt b/147/CH8/EX8.9/Result8_9.txt
new file mode 100644
index 000000000..46fe0d76a
--- /dev/null
+++ b/147/CH8/EX8.9/Result8_9.txt
@@ -0,0 +1,5 @@
+(a) Icq = 2.333 mA
+
+(b) Rb for Si device = 490.3 k ohm
+
+(c) Rb for Ge device = 504.0 k ohm \ No newline at end of file