Chapter9 - Cathode Ray Oscilloscope

Example 9.14.1 - page : 9-45

In [3]:
# peak to peak voltage and rms voltage
vdv=1 # V/div
n=6.8 #no. of divisions
Vpp=vdv*n #peak to peak voltage in V
vrms=Vpp/(2*(2)**(1.0/2)) #rms voltage in V
print "Peak to peak voltage is ",Vpp," V"
print "rms voltage is ",round(vrms,4)," V"

Peak to peak voltage is  6.8  V
rms voltage is  2.4042  V

Example 9.14.2 - page : 9-46

In [4]:
#Time interval
vdv=2 # V per division in micro seconds/div
n=2 #no. of divisions
Tint=vdv*n #peak to peak voltage in V
print "Time interval is ",Tint," micro seconds"

Time interval is  4  micro seconds

Example 9.14.3 - page : 9-46

In [6]:
# period and frequency
vdv=2 #volts per division in micro seconds/div
n=12 #no. of divisions
Tp=vdv*n # period in micro seconds
f=1/(Tp*10**-3) #frequency in kHz
print "Period is ",Tp," micro seconds"
print "Frequency is ",round(f,2)," kHz"

Period is  24  micro seconds
Frequency is  41.67  kHz

Example 9.14.4 - page : 9-47

In [7]:
#Peak to peak voltage and frequency
vdv1=0.5 #volts per division in V/div
nv=3 #no. of divisions
nh=4 #numbers of horizontal divisions
Vpp=vdv1*nv #peak to peak voltage in V
vdv2=2 # time division in micro seconds per divisions
Tp=vdv2*nh # period in micro seconds
f=1/(Tp*10**-3) #frequency in kHz
print "Peak to peak voltage is ",Vpp," V"
print "Period is ",Tp," micro seconds"
print "Frequency is ",f," kHz"

Peak to peak voltage is  1.5  V
Period is  8  micro seconds
Frequency is  125.0  kHz

Example 9.17.1 - page : 9-67

In [9]:
#bandwidth
#given data :
Trs=12 #in micro sec
Trd=15 #in micro sec
Tro=(Trd**2-Trs**2)**(1.0/2) 
K=0.35 # constant
BW=(K/Tro)*10**3 
print "Bandwidth, BW =",round(BW,2), " kHz"

Bandwidth, BW = 38.89  kHz

Example 9.17.2 - page : 9-68

In [10]:
#Rise time
#given data :
BW=10*10**6 # in Hz
tr=(0.35/BW)*10**9 
print "Rise time, tr = ",tr, " ns"

Rise time, tr =  35.0  ns

Example 9.17.3 - page : 9-68

In [12]:
# rise time
#given data :
Tro=10 #in micro sec
Trd=13 #in micro sec
Trs=(Trd**2-Tro**2)**(1.0/2) 
print "Actual rise time, Trs = ",round(Trs,2)," ns"

Actual rise time, Trs =  8.31  ns

Example 9.17.4 - page : 9-68

In [14]:
# Rise time
#given data :
Tro=10 #in micro sec
Trd=15 #in micro sec
Trs=(Trd**2-Tro**2)**(1.0/2)
print "Actual rise time, Trs = ",round(Trs,2)," ns"

Actual rise time, Trs =  11.18  ns

Example 9.17.5 - page : 9-68

In [16]:
# Rise time
#given data :
Trs=12 #in micro sec
Trd=30 #in micro sec
BW=20*10**6 # in Hz
K=0.35 # constant
Tro=(K/BW)*10**9 
Trs=(Trd**2-Tro**2)**(1.0/2)
print "Actual rise time, Trs = ",round(Trs,2)," ns"

Actual rise time, Trs =  24.37  ns

Example 9.17.6 - page : 9-69

In [18]:
# capacitance
#given data :
K=10 # constant
C2=35*10**-12 
C1=(C2/(K-1))*10**12 
print "Capacitance, C1 = ",round(C1,2)," pF"

Capacitance, C1 =  3.89  pF

Example 9.17.7 - page : 9-69

In [19]:
# impedance of CRO
K=10 
vin=1 #vpp 
vout=0.1 #in vpp
c1=2 # in pF
c2=c1*(K-1) #CAPACITANCE IN Pf
print "Capacitance is ",c2," pF"

Capacitance is  18  pF

Example 9.17.8 - page : 9-70

In [21]:
# sensivity
n=2 #divisions
f=50.0 #in MHz
t=(1/f)*10**3 #time in nanao seconds
mdv=t/4 #in ns/div
mtds=mdv*n # in ns/div
print "Minimum time/div is ",mdv," ns/div"
print "Minimum time/div setting is ",mtds," ns/div"

Minimum time/div is  5.0  ns/div
Minimum time/div setting is  10.0  ns/div

Example 9.17.9 - page : 9-70

In [24]:
# rise time
#given data :
Trs=21 #in micro-sec
K=0.35 # constant
BW=50*10**6 # in Hz
Tro=(K/BW)*10**9 
Trd=(Trs**2+Tro**2)**(1.0/2)
print "Rise time, Tro = ",round(Trd,0)," ns"

Rise time, Tro =  22.0  ns