Chapter13-Radio

Ex1-pg229

In [1]:
##Ex:13.1
import math
c=3.*10**8;
wl=15.;
f=c/wl;
print'%s %.2f %s'%("The frequency = ",f," Hz");

The frequency =  20000000.00  Hz

Ex2-pg229

In [2]:
##Ex:13.2
import math
c=3.*10**8;
f=150.*10**6;
wl=c/f;
print'%s %.2f %s'%("The wavelength =",wl," m");

The wavelength = 2.00  m

Ex3-pg229

In [4]:
##Ex:13.3
import math
wl=8.;
f=30.*10**6;
v=f*wl;
print'%s %.2f %s'%("The veocity of propagation = ",v," m/s");

The veocity of propagation =  240000000.00  m/s

Ex4-pg230

In [5]:
##Ex:13.4
import math
f_rf=162.5;##in kHz
f_af=1.25;##in kHz
f_bfo_max=f_rf+f_af;
f_bfo_min=f_rf-f_af;
print'%s %.2f %s %.2f %s '%("The two possible BFO freq. = ",f_bfo_max," kHz" and "",f_bfo_min,"kHz");

The two possible BFO freq. =  163.75  161.25 kHz

Ex5-pg234

In [6]:
##Ex:13.5
import math
f_rf_1=88.;##in MHz
f_rf_2=108.;##in MHz
f_if=10.7;##in MHz
f_lo_1=f_rf_1+f_if;
f_lo_2=f_rf_2+f_if;
print'%s %.2f %s %.2f %s '%("The range local oscillator be tuned = ",f_lo_1," MHz" and  "",f_lo_2," MHz");

The range local oscillator be tuned =  98.70  118.70  MHz

Ex6-pg238

In [7]:
##Ex:13.6
import math
f_rf_1=88.;##in MHz
f_rf_2=108.;##in MHz
f_if=10.7;##in MHz
f_lo_1=f_rf_1+f_if;
f_lo_2=f_rf_2+f_if;
print'%s %.2f %s %.2f %s '%("The range local oscillator be tuned = ",f_lo_1," MHz" and "",f_lo_2,"MHz");

The range local oscillator be tuned =  98.70  118.70 MHz

Ex7-pg239

In [8]:
##Ex:13.7
import math
r=12.;##in ohms
i=0.5;##in amps
P_r=i*i*r;##in W
print'%s %.2f %s'%("Power radiated = ",P_r," W");

Power radiated =  3.00  W

Ex8-pg239

In [9]:
##Ex:13.8
import math
r=2.;##in ohms
i=0.5;##in amps
P_r=4.;##in W
P_loss=i*i*r;
P_eff=(P_r/(P_r+P_loss))*100.;
print'%s %.2f %s'%("The power loss = ",P_loss," W");
print'%s %.2f %s'%("\n The power loss = ",P_eff,"");

The power loss =  0.50  W

 The power loss =  88.89