7 files changed, 297 insertions, 0 deletions
diff --git a/881/CH4/EX4.1/exa4_1.sce b/881/CH4/EX4.1/exa4_1.sce
new file mode 100755
index 000000000..cb497c803
--- /dev/null
+++ b/881/CH4/EX4.1/exa4_1.sce
@@ -0,0 +1,51 @@
+clc;
+//Example 4.1
+//Page no 118
+
+disp("Given: For and AM DSBFC modulator with a carrier frequency Fc=100kHz and a maximum modulating signal frequency of Fm(max)=5kHz.");
+
+//solution
+
+Fc=100*(10^3);
+Fm=5*(10^3);
+fm=3*(10^3);
+
+//(a)
+
+disp("(a)The lower sideband extends from the lowest possible lower side frequency to the carrier frequency or ");
+
+lsb=(Fc-Fm); 
+
+disp("kHz",(Fc/(10^3)),"kHz to",(lsb/(10^3)),"LSB = ");
+
+disp("The upper sideband extends from the carrier frequency to the highest possible upper side frequency is ");
+
+usb=(Fc+Fm);
+
+disp("kHz",(usb/(10^3)),"kHz to",(Fc/(10^3)),"USB = ");
+
+//(b)
+
+disp("(b)The bandwidth is equal to the difference between the maximum upper side frequency and the minimum lower side frequency. ");
+
+b=2*Fm;
+
+disp("kHz",(b/(10^3)),"B = ");
+
+//(c)
+
+disp("(c)The upper side frequency is the sum of the carrier and modulating frequency.");
+
+Fu=Fc+fm;
+
+disp("kHz",(Fu/(10^3)),"Fusf = ");
+
+disp("The lower side frequency is the difference between the carrier and modulating frequency.");
+
+Fl=Fc-fm;
+
+disp("kHz",(Fl/(10^3)),"Flsf = ");
+
+//(d)
+
+disp("(d)The output frequency spectrum is shown in figure.");
diff --git a/881/CH4/EX4.2/exa4_2.sce b/881/CH4/EX4.2/exa4_2.sce
new file mode 100755
index 000000000..95093144a
--- /dev/null
+++ b/881/CH4/EX4.2/exa4_2.sce
@@ -0,0 +1,48 @@
+clc;
+//Example 4.2
+//Page no 123
+
+
+//solution
+
+Fc=500; //kHz
+Fm=10; //kHz
+Ec=20;
+Em=7.5;
+
+disp("(a)The upper and lower side frequencies are simply the sum and difference frequencies, respectively ");
+
+fu=Fc+Fm;
+fl=Fc-Fm;
+
+disp('kHz',fl,'kHz and Flsf = ',fu,"Fusf = ");
+
+//(b)
+
+disp("(b)The modulation coefficient is determined from equation 4-1 (refer pgno 120)");
+
+m=Em/Ec;
+
+disp(m,"m = ");
+
+disp("Percent modulation is determine from equation 4-2 (refer pgno 120)");
+
+M=100*m;
+
+disp('%',M,"M = ");
+//(c)
+
+disp("(c)The peak amplitude of the modulated carrier and the upper and lower side frequencies is ");
+
+eu=((m*Ec)/2);
+
+disp('Vp',eu,"Eusf(modulated) = ");
+
+//(d)
+
+disp("(d)The maximum and minimum amplitude of the envelope are, ");
+
+Vm=Ec+Em;
+vm=Ec-Em;
+
+disp('Vp',vm,'Vp and Vmin = ',Vm,"Vmax = ");
diff --git a/881/CH4/EX4.3/exa4_3.sce b/881/CH4/EX4.3/exa4_3.sce
new file mode 100755
index 000000000..1351260d4
--- /dev/null
+++ b/881/CH4/EX4.3/exa4_3.sce
@@ -0,0 +1,32 @@
+clc;
+//Example 4.3
+//Page no 128
+//solution
+
+Fc=1; //MHz
+Fm=5; //kHz
+M=60; //%
+m=(M/100); 
+Pc=6; //KW
+
+
+//(a)
+
+disp("(a)Total average power delivered to the load ");
+
+Rl=(Pc*[1+m^2/2]);
+
+disp('KW',Rl,"Rl = ");
+
+//(b)
+
+disp("(b)The modulation signal power ");
+
+Vs=sqrt(100*(10^3)*Rl);
+ 
+disp('KV',(Vs/(10^3)),"Vs(RMS) = ");
+
+a=Vs*sqrt(2);
+
+disp('KV',(a/(10^3)),"Therefore, peak value of modulation signal =")
+
diff --git a/881/CH4/EX4.4/exa4_4.sce b/881/CH4/EX4.4/exa4_4.sce
new file mode 100755
index 000000000..fd67501b3
--- /dev/null
+++ b/881/CH4/EX4.4/exa4_4.sce
@@ -0,0 +1,64 @@
+clc;
+//Example 4.4
+//Page no 128
+
+Vc=10; //Vp
+m=1;
+Rl=10;
+m1=0.5;
+
+//(a)
+
+disp("(a)The carrier power is found by substituting into equation 4-18 (pgno 126): ");
+
+Pc=((Rl^2)/(2*Rl));
+
+disp('W',Pc,"Pc = ");
+
+disp("The upper and lower sideband power is found by substituting into equation 4-21 (pgno 127):");
+
+P=(((m^2)*Pc)/4);
+
+disp('W',P,"Pusb = Plsb = ");
+
+//(b)
+
+disp("(b)The total sideband power is ");
+
+Ps=(((m^2)*Pc)/2);
+
+disp('W',Ps,"Psbt = ");
+
+//(c)
+
+disp("(c)The total power in the modulated is found by substituting into equation 4-25 (pgno 127)");
+
+Pt=(5*[1+(m^2)/2]);
+
+disp('W',Pt,"Pt = ");
+
+//(d)
+
+disp("(d)The carrier power is found by substituting into equation 4-18 ");
+
+Pc1=Pc;
+
+disp('W',Pc1,"Pc ");
+
+disp("The upper and lower sideband power is found by substituting into equation 4-21 (pgno 127):");
+
+P1=(((m1^2)*Pc)/4);
+
+disp('W',P1,"Pusb = Plsb = ");
+
+disp("The total sideband power is ");
+
+Ps1=(((m1^2)*Pc)/2);
+
+disp('W',Ps1,"Psbt = ");
+
+disp("The total power in the modulated is found by substituting into equation 4-25 (pgno 127)");
+
+Pt1=(5*[1+(m1^2)/2]);
+
+disp('W',Pt1,"Pt = ");
diff --git a/881/CH4/EX4.5/exa4_5.sce b/881/CH4/EX4.5/exa4_5.sce
new file mode 100755
index 000000000..51d54d67d
--- /dev/null
+++ b/881/CH4/EX4.5/exa4_5.sce
@@ -0,0 +1,37 @@
+clc;
+//Example 4.5
+//Page no 131
+
+//Solution
+
+Rl=100; //ohm
+Fc=1;  //MHz
+Fm1=2; //kHz
+Fm2=3; //kHz
+Fm3=5; //kHz
+Ec=100; //V
+Em1=10; //V
+Em2=20; //V
+Em3=30; //V
+
+m1=(Em1/Ec);
+
+disp(m1,"m1 = ");
+
+m2=(Em2/Ec);
+
+disp(m2,"m1 = ");
+
+m3=(Em3/Ec);
+
+disp(m3,"m1 = ");
+
+m=sqrt((m1^2)+(m2^2)+(m3^2));
+
+disp(m,"Overall modulation index m = ");
+
+disp("Power in both the upper and lower sideband is same, which is given by ");
+
+Psb=((Ec^2*m^2)/(2*Rl*4));
+
+disp('W',Psb,"Psb = ");
diff --git a/881/CH4/EX4.6/exa4_6.sce b/881/CH4/EX4.6/exa4_6.sce
new file mode 100755
index 000000000..369cecb2c
--- /dev/null
+++ b/881/CH4/EX4.6/exa4_6.sce
@@ -0,0 +1,31 @@
+clc;
+//Example 4.6
+//Page no 133
+//Solution
+
+m=0.8;
+Aq=100;
+Fc=500; //kHz
+Vc=5*(10^-3); //mV
+Fm=1000; //Hz
+
+//(a)
+
+disp("(a)Substituting into equation 4-34(pgno 132), ");
+
+Am=Aq*(1+m);
+
+disp(Am," Amax = ");
+
+am=Aq*(1-m);
+
+disp(am,"Amin = ");
+
+//(b)
+
+Vom=Am*Vc;
+
+vom=am*Vc;
+
+disp('V',Vom,"(b)Vout(max) =  ");
+disp('V',vom,"Vout(min) =  ");
diff --git a/881/CH4/EX4.7/exa4_7.sce b/881/CH4/EX4.7/exa4_7.sce
new file mode 100755
index 000000000..032db4f7e
--- /dev/null
+++ b/881/CH4/EX4.7/exa4_7.sce
@@ -0,0 +1,34 @@
+clc;
+//Example 4.7
+//Page no 140
+//solution
+
+//(a)
+
+V=12; //dc
+Vm=2; //Vp
+Fm=4; //kHz
+Vb=4; //dc
+R1=100*(10^3); //kohm
+C1=0.001*(10^-6); //uF
+
+//(a)
+
+disp("(a)The carrier frequency is determine from equation 4-36(refer pgno 137): ");
+
+fc=(1/(R1*C1));
+Fc=fc/(10^2)
+
+disp('kHz',Fc,"fc =  ");
+
+//(b)
+
+disp("(b)The upper and lower side frequency are simply the sum and difference frequencies between the carrier and the modulating signal. ");
+
+fu=Fc+Fm;
+
+disp('kHz',fu,"Fusf =  ");
+
+fl=Fc-Fm;
+
+disp('kHz',fl,"Flsf =  ");