The use of this tool is quite straightforward, simply key in the values of a, b, g, h and t into the cells B6 through B10. Key in the frequency range into the cells B13 and B14. Note that the units of frequency is rad/time. The Nyquist plot is generated.

Lets say we wish to obtain the Nyquist plot of e^-4s/(1 + 2s), from 0.01 rad/s to 100 rad/s. We have

a = 1,

b = 0,

g =1,

h = 2 and

t = 4.

Key in these values and the range, the Nyquist plot is shown below.