Chapter6 - Digital Frequency Meter

Example 6.17.1 - page6-26

In [2]:
# Desired gate time
#Given data :
r=0.1         #in Hz
D=1/r         #in seconds
print "The desired gate time, D = ", D," seconds"

The desired gate time, D =  10.0  seconds

Example 6.17.2 - page6-27

In [3]:
# Error in measurement
f1=1.0 # in Mhz
f2=200.0 #in kHz
per=(200*10**-3)*100 # percentage error that printlay may indicate 4 micro seconds or 6 micro seconds
per1=(1/50.0)*100 #percentage error after 10 times improvement
print "Display may indicate 4 us or 6 us, percentage error is ", per," %"
print "Percentage error after 10 times improvement is ", per1," %"

Display may indicate 4 us or 6 us, percentage error is  20.0  %
Percentage error after 10 times improvement is  2.0  %

Example 6.17.3 - page6-27

In [7]:
#  Measurement Accuracy
#Given data :
f=400.0         #Hz
time_accuracy=10**-8         # seconds
display_accuracy=1         #(+ve or -Ve)
t=10         # seconds
period=1/f*10**3          #ms
Accuracy= 1+((period)/10)         #ms
print "accuracy is ±",Accuracy," ms"

accuracy is ± 1.25  ms