Presumably the roller coaster could be used for
a vari-tap, but then that means that the whole coil
will always be in circuit.

Time for a quikc .XLS for all bands.....

"Roy Lewallen" wrote in message
...
A common solution is to use a parallel tuned circuit, approximately
resonant, with inductor and capacitor reactances of a couple hundred
ohms or so, and the capacitor being adjustable. Connect one end of the
network to ground and the other to the antenna. Connect the feedline
between ground and a tap near the bottom of the coil. Alternately adjust
the tap position and the variable capacitor for the best impedance match.

Roy Lewallen, W7EL

Rick Karlquist N6RK wrote:
"Airy R. Bean" wrote in message
...

What do I do, however, for those frequencies for which it is close
to a half wave? PI network? Or L network?


An L network with reactances of several hundred ohms for
both inductor and capacitor.

Rick N6RK