On Mon, 12 Nov 2007 10:51:58 -0500, Ed Cregger
wrote:

A 108" whip tuned with an electronic autotuner at the base, on the
trailer hitch attached to an average car should be just as (was gonna
use the words efficient and effective - but thought better of it) as a
short little whip mounted in PVC pipe at the same location, but using a
mechanical tuner (screwdriver) instead of an electronic autotuner such
as an AH-4.

Hi Ed,

This is a bit garbled, but the sense is there.

You are comparing a bad installation to a bad installation - yes one
will be as efficient/effective as the other.

The tuner at the base of the whip has invested resonance in the wrong
place. A coil at the base of a whip also invests resonance in the
wrong place. A coil higher in the whip invests resonance in the
better places by degree.

Ostensibly, the premium degree of coil placement is one half to two
thirds the way up the whip. A screwdriver antenna attempts to make
this resonance investment. If you will note, the coil section falls
between a lower tube and an upper whip.

There is a world of discussion as to why it is better that I will
leave to others to fill in.

73's
Richard Clark, KB7QHC