7 files changed, 123 insertions, 0 deletions
diff --git a/2825/CH15/EX15.1/Ex15_1.sce b/2825/CH15/EX15.1/Ex15_1.sce
new file mode 100755
index 000000000..d69056da3
--- /dev/null
+++ b/2825/CH15/EX15.1/Ex15_1.sce
@@ -0,0 +1,9 @@
+//Ex15_1 Pg-773
+clc
+
+Pc=10000 //carrier input power in watt
+m=30/100 //modulation of 30%
+
+disp("Total power = carrier power*(1+m^2/2)")
+Pt=Pc*(1+m^2/2) //total power
+printf("             = %.2f kW",Pt*1e-3)
diff --git a/2825/CH15/EX15.2/Ex15_2.sce b/2825/CH15/EX15.2/Ex15_2.sce
new file mode 100755
index 000000000..8fdf963fd
--- /dev/null
+++ b/2825/CH15/EX15.2/Ex15_2.sce
@@ -0,0 +1,12 @@
+//Ex15_2 Pg-774
+clc
+
+Ic=100 //carrier current in A
+m=80/100 //modulation of 80%
+
+disp("Total current = carrier current*(1+m^2/2)")
+It=Ic*sqrt(1+m^2/2) //total power
+printf("               = %.1f A \n",It)
+
+change_I=It-Ic //change in current
+printf("Therefore, increase in current due to modulation = %.1f A",change_I)
diff --git a/2825/CH15/EX15.3/Ex15_3.sce b/2825/CH15/EX15.3/Ex15_3.sce
new file mode 100755
index 000000000..82f9b4436
--- /dev/null
+++ b/2825/CH15/EX15.3/Ex15_3.sce
@@ -0,0 +1,26 @@
+//Ex15_3 Pg-774
+clc
+
+Em=5 //modulated wave amplitude
+Ec=100 //carrier wave amplitude
+Fm=50 //frequency of modulated wave
+Fc=10*10^(3) //frequency of carrier wave 
+
+disp("(1) Modulation Factor")
+m=Em/Ec //modulation factor
+per_m=m*100 //modulation factor in percentage
+printf("                m = %.0f %%",per_m)
+
+disp("(2) Amplitude of each sideband = m*Ec/2")
+Amp=m*Ec/2 //amplitude of each sideband
+printf("                = %.1f",Amp)
+
+USB=Fc+Fm //upper side band
+LSB=Fc-Fm //lower side band
+disp("(3) Frequenc of sidebands")
+printf("        USB = %.0f Hz \n",USB)
+printf("        LSB = %.0f Hz \n",LSB)
+
+disp("(4) Bandwidth of the wave")
+BW=2*Fm //Bandwidth
+printf("        BW = %.0f",BW)
diff --git a/2825/CH15/EX15.4/Ex15_4.sce b/2825/CH15/EX15.4/Ex15_4.sce
new file mode 100755
index 000000000..aa2a74f9a
--- /dev/null
+++ b/2825/CH15/EX15.4/Ex15_4.sce
@@ -0,0 +1,10 @@
+//Ex15_4 Pg-774
+clc
+
+Vmax=600 //peak to peak voltage
+Vmin=100 //valley to valley voltage
+
+disp("From figure 15.49, we have")
+m=(Vmax-Vmin)/(Vmax+Vmin) //modulation factor
+per_m=m*100 //modulation factor in percentage
+printf(" \n Modulation factor = %.1f %%",per_m )
diff --git a/2825/CH15/EX15.5/Ex15_5.sce b/2825/CH15/EX15.5/Ex15_5.sce
new file mode 100755
index 000000000..7f5b43b61
--- /dev/null
+++ b/2825/CH15/EX15.5/Ex15_5.sce
@@ -0,0 +1,29 @@
+//Ex15_5 Pg-775
+clc
+
+disp("The standard equation of AM wave is")
+disp(" e = Ec*(1+m*sin(omega_m*t)*sin(omega_c*t)) -->eqn 1")
+disp("Given the equation")
+disp(" e = 20*(1+0.7*sin(6280*t)*sin(628000*t))   --eqn 2")
+disp("Comparing eqn 1 and eqn 2 one obtains")
+disp("(1) Modulation factor, m = 0.7")
+m=0.7 //modulation factor
+disp("(2) Carrier Amplitude, Ec = 20 V")
+Ec=20 //carrier wave amplitude in V
+disp("(3) omega_m = 6280")
+omega_m=6280 //modulating frequency
+Fm=omega_m/(2*%pi) //signal frequency
+printf("    Signal frequency = %.0f kHz \n\n",Fm*1e-3)
+
+omega_c=628000 //carrier frequency in Hz
+Fc=omega_c/(2*%pi) 
+printf("(4) Signal frequency = %.0f kHz \n\n",Fc*1e-3)
+
+Emax=Ec+m*Ec //minimum amplitude of wave
+printf("(5) Emax = %.0f V \n\n",Emax)
+
+Emin=Ec-m*Ec //minimum amplitude of wave
+printf("(5) Emin = %.0f V\n\n",Emin)
+
+BW=2*Fm //Bandwidth
+printf("(6) BW = %.0f kHZ",BW*1e-3)
diff --git a/2825/CH15/EX15.6/Ex15_6.sce b/2825/CH15/EX15.6/Ex15_6.sce
new file mode 100755
index 000000000..9f8be3af8
--- /dev/null
+++ b/2825/CH15/EX15.6/Ex15_6.sce
@@ -0,0 +1,16 @@
+//Ex15_6 Pg-776
+clc
+
+Pc=10000 //carrier power in watt
+m=0.9 //modulation factor
+disp("We have")
+
+disp("Total power = carrier power*(1+m^2/2)")
+Pt=Pc*(1+m^2/2) //total power
+printf("             = %.0f kW \n\n",Pt*1e-3)
+
+printf("This will be the maximum power handeled by the transmitter.\n Now,increased unmodulated carrier power can be obtained by \n\n")
+m=40/100 //modulation in terms of percentage
+Pt=14000 //total power
+Pc=Pt/(1+m^2/2) //neew carrier power
+printf("        Pc = %.2f kW",Pc*1e-3)
diff --git a/2825/CH15/EX15.7/Ex15_7.sce b/2825/CH15/EX15.7/Ex15_7.sce
new file mode 100755
index 000000000..35d15103b
--- /dev/null
+++ b/2825/CH15/EX15.7/Ex15_7.sce
@@ -0,0 +1,21 @@
+//Ex15_7 Pg-776
+clc
+
+disp("Given the equation")
+printf("\n E = 100*sin(628000*t) + 25*sin(621720*t) \n   - 25*cos(634280*t)) \n")
+ m=50/100 //modulation factor in percentage
+ Ec=100 //carrier wave amplitude in V
+ Em=10 //modulated wave amplitude in V
+Fc=100000 //carier frequency in Hz
+Fm=1000 //modulating frequency in Hz
+pi=3.14 
+
+omega_c=2*pi*Fc //carier frequency
+omega_m=2*pi*Em //modulating frequency 
+
+disp("Now,putting these equation in the standard equations for modulated voltage wave,")
+disp("  e = Ec*sin(omega_c*t)+m*Ec/2*cos(omega_c-omega_m)*t-m*Ec/2*cos(omega_c-omega_m)*t")
+USB=omega_c+omega_m //upper sideband
+LSB=omega_c-omega_m //lower sideband
+mEc=m*Ec/2
+printf("\n     = 100*sin(628000*t) + %.0f*sin(%.0f*t) \n      - %.0f*cos(%.0f*t))",mEc,USB,mEc,LSB)