Dr. Slick wrote;
"Well, our super J-pole is bearing our yagi in ALL directions, even in
the forward lobe."

It`s possible.

This thread pits a "Super J-Pole" with 6 dBd gain against a "Yagi-Uda"
with 2.85 to 17.85 dBd gain (5 to 20 dBi), depending on construction.
So, it could be true for some 2-element Yagi or it could untrue for a
Yagi with 3 or more elements. A 3-element Yagi may give about 5 or 6 dBd
gain.

The "ARRL Antenna Book" gives the details. In my 19th edition, the Super
J-Pole is asid to give 6 dB gain over a 1/4-wave whip on page 16-27.

The whip with a perfect reflection (a ground-plane antenna) is said on
page 13-10 to be equivalent to a 1/2-wave dipole in free-space: "---the
image of a vertical antenna is in phase with the vertical radiator". The
whip with the perfect reflection is thus identical to a 1/2-wave in
free-space in performance. Gain of the ground-plane is 0 dBd or +2.15
dBi.

Best regards, Richard Harrison, KB5WZI

Richard Harrison wrote:
Dr. Slick wrote;
"Well, our super J-pole is bearing our yagi in ALL directions, even
in
the forward lobe."

It`s possible.


it's true. But this doesn't mean that
it's going to beat ALL Yagis, which
is what some people have thought this
thread was all about. Just THIS 180
degree Yagi, with 11 dB F/B ratio.



This thread pits a "Super J-Pole" with 6 dBd gain against a
"Yagi-Uda"
with 2.85 to 17.85 dBd gain (5 to 20 dBi), depending on construction.


6 dBd would be about 8.15 dBi, which is not
the case here.

The Super J-pole is 5.5 dBi or 3.35 dBd.

This particular Yagi is about 4.5 dBi
in the front lobe, which was a compromise
to get the 180 degree pattern (and 11dB F/B).





The "ARRL Antenna Book" gives the details. In my 19th edition, the
Super
J-Pole is asid to give 6 dB gain over a 1/4-wave whip on page 16-27.


Really? If we say the 1/4 wave is 2.15 dBi, then
the Super J is 3.35dBd, omni.

So i'm not sure where they got these numbers,
or if we are talking about the same thing.


Slick