Edward A. Feustel wrote:
. . .
Since on the MFJ, the inductor is the shunting element, this is a high-pass
network and
helps to encourage harmonics.

What's the mechanism by which a high-pass network "encourages"
harmonics? Because a network with a flat frequency frequency response
has the same high frequency response as a high-pass network, it follows
that a network with a flat frequency response must "encourage" harmonics
also. Why?

Roy Lewallen, W7EL