Chapter 10: Power Amplifiers

Example 10.1 Page No.345

#Given
RL=16                                                     # Ohms, load resistance
RLd=10000.0                                         # Ohms ,effective load resistance

#Calculation
import math
N12=math.sqrt(RLd/RL)                               #N12=N1/N2

# Result
print " The Transformer Turns Ratio is N1/N2",N12,":1"

 The Transformer Turns Ratio is N1/N2 25.0 :1

Example 10.2 Page No.345

#Given Circuit Data
Rl=8.0                                        #Ohms, load resistance
N12=15.0                                  #N12=N1/N2, transformer turns ratio

#Calculation
Rld=(N12)**2*Rl                 #effective resistance

# Result
print " The Effective Resistance seen looking into the Primary, Rld =  ",Rld/10**3,"k ohm"

Example 10.3 Page No.353

I1=15                                            #A
I2=1.5                                           #A
I3=1.2                                           #A
I4=0.5                                           #A

#Calculation
D2=(I2/I1)*100                               #percentage harmonic distribution of component  2
D3=(I3/I1)*100                               #percentage harmonic distribution of component  3
D4=(I4/I1)*100                               #percentage harmonic distribution of component  4

#Result
print " The Second Harmonic Distortion is, D2 =  percent .",D2
print " The Third  Harmonic Distortion is, D3 =  percent .",D3
print " The Fourth Harmonic Distortion is, D4 =  percent .",round(D4,2)

#(b)
import math
P1=1        #say

#Calculation
D=math.sqrt(D2**2+D3**2+D4**2)    #Distortion Factor
P=(1+(D/100)**2)*P1
Pi=((P-P1)/P1)*100

#Result
print "The Percentage Increase in Power because of Distortion is, Pi (in percent)= ",round(Pi,2)

 The Second Harmonic Distortion is, D2 =  percent . 10.0
 The Third  Harmonic Distortion is, D3 =  percent . 8.0
 The Fourth Harmonic Distortion is, D4 =  percent . 3.33
The Percentage Increase in Power because of Distortion is, Pi (in percent)=  1.75