Need multiple revolutions on radar plot in Excel

[Guest]

I am trying to plot an Archimedes spiral with the radar plot in Excel and can
only obtain one revolution. I need multiple revolutions and would also like
to have multiple arms in the spiral.

 

[Herbert Seidenberg]

Create a series for the Category(X) axis labels
that goes from 0 to almost 2*pi()
Just how close to 2*pi() depends on the number of data points.
Very tricky.
Generate the radius values for these radians and plot.
For the second revolution,
generate the radius values for 2*pi() to almost 4*pi() and plot,
using the original Category(X) axis labels.
The lines will not join correctly, so just show markers.
To have the lines join smoothly, use XY scatter plot instead.
Convert to X, Y values with
=COS(radians)*radius and
=SIN(radians)*radius
Use a different series for each revolution.