Dave wrote:

The trick is to make

R = sqrt(L/C)

then the impedance is real everywhere. You can use any old values for L:
and C, as long as you make R=sqrt(L/C);


That equation is obviously know from transmission lines too..

Another interesting thing about this general topology is that, except
for the special case where R^2 = L/C (the constant impedance case), the
resonant frequency is 1 / (2 * pi * sqrt(LC)) if and only if the two
resistors are equal in value. Otherwise it's at some other frequency
depending on the R values.

Roy Lewallen, W7EL