Chapter 6: Amplification

Example 6.1, Page 92

In [11]:
#Initialisation
Ri=1000                    #Input Resistance of amplifier in Ohm
Rs=100                    #Output Resistance of sensor in Ohm
Rl=50                     #Load Resistance
Ro=10                    #Output Resistance of amplifier in Ohm
Av=10                     #Voltage gain
Vs=2                       #Sensor voltage

#Calculation
Vi=Ri*Vs*(Rs+Ri)**-1               #Input Voltage of Amplifier
Vo=Av*Vi*Rl*(Ro+Rl)**-1               #Output Voltage of Amplifier

#Result
print'Ouput voltage of and amplifier = %.1f V'%Vo

Ouput voltage of and amplifier = 15.2 V

Example 6.2, Page 93

In [10]:
#Initialisation
Vo=15.2               #Output Voltage of Amplifier
Vi=1.82               #Input Voltage of Amplifier

#Calculation
Av=Vo/Vi                     #Voltage gain

#Result
print'Voltage Gain, Av = %.2f'%Av

Voltage Gain, Av = 8.35

Example 6.3, Page 94

In [9]:
#Initialisation
Av=10                     #Voltage gain
Vi=2                      #Input Voltage of Amplifier
Rl=50                     #Load Resistance
Ro=0                    #Output Resistance of amplifier in Ohm


#Calculation
Vo=Av*Vi*Rl/(Ro+Rl)               #Output Voltage of Amplifier

#Result
print'Ouput voltage of and amplifier = %.1f V'%Vo

Ouput voltage of and amplifier = 20.0 V

Example 6.4, Page 96

In [8]:
#Initialisation
Vo=15.2                               #Output Voltage
Rl=50                                 #Load Resistance

#Calculation 
Po=(Vo**2)/Rl                           #Output Power

#Result
print'Output Power, Po = %.1f W'%Po

Output Power, Po = 4.6 W

Example 6.5, Page 98

In [18]:
#Initialisation
Vi=1.82                     #Input Voltage of Amplifier
Ri=1000                    #Input Resistance of amplifier in Ohm
Vo=15.2                     #Output Voltage of Amplifier
Rl=50                     #Load Resistance


#Calculation
Pi=(Vi**2)*Ri**-1                #Input Power in Watt
Po=(Vo**2)*Rl**-1                #Output Power in Watt
Ap=Po/Pi                          #Power Gain
 

#Result
print'Power Gain, Ap = %d'%Ap            #wrong answer in textbook     
             

Power Gain, Ap = 1395

Example 6.6, Page 99

In [5]:
import math
#Initialisation
P=1400                          #Power gain

#Calculation
pdb=10*math.log10(P)                 #Power Gain in dB

#Result
print'Power Gain (dB) = %.1f dB'%pdb

Power Gain (dB) = 31.5 dB
In [ ]: