John Smith wrote:
Gene Fuller wrote:

...
The patent, US 7187335, is a real hoot. I especially like the part
where he describes doubling the bandwidth by adding a parasitic
winding intertwined with the base coil helix.

Do you suppose his antenna is in equilibrium? Could proper application
of Artsian-Gaussian theory improve it even more?



73,
Gene
W4SZ

What? You don't see cutting the capacitance between winding turns as
causing some measurable effect which in turn affects a property of the
antenna proper?

Thicker conductor(s) usually means a measurable gain in bandwith, with a
parasitic element in such close proximity to the major element, a gain
in bandwidth is not that difficult to propose and attempt to
prove/disprove.

Regards,
JS

John,

The effects you mention may have some impact on bandwidth, but they
don't double it. And the capacitance probably increases, not decreases.
Placing an extra conductor between two capacitor plates increases the
capacitance. At the same time placing a grounded shield between two
capacitor plates reduces or eliminates the coupling between the original
plates. It is not clear to me which effect would dominate in this case.
In either case it is unlikely to be very important.

Lots of people understand how to make an antenna broadband; simply add
resistance. This is not always "bad". It is merely a choice.

Just for grins I did a little EZNEC experiment. I started with a base
loaded monopole that used a generated helix as the loading coil. I
adjusted and resonated the system to SWR = 1 and took a look at the
bandwidth. I arbitrarily took SWR = 2 as the bandwidth limits. I then
added a parasitic winding between the turns of the helix. This winding
was not connected to anything. I reran the simulations.

What I found was interesting, but not surprising.

When the wires were treated as lossless, there was virtually no
difference in bandwidth or any other parameter. The parasitic winding
had essentially no impact.

When I changed the wires to copper, the bandwidth increased in both
cases. However, in the case with the parasitic winding the new bandwidth
was 2.5 times as large as the case without the extra winding. The
resonant input impedance was also about 2.5 times larger.

There is only one plausible explanation for this observation. The
parasitic winding adds loss to the antenna system. I won't claim this is
"bad". Depends on the characteristics desired.

The bottom line is that there is no wondrous invention here. Either
Vincent knew about this effect and chose to ignore it, or he did not
understand what was happening. The capacitance explanation is just baloney.

73,
Gene
W4SZ

On Oct 9, 11:35 pm, John Smith wrote:
art wrote:
www.newswise.com/articles/view/532935

Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made
A$$'es out of all the "experts" and continues to do so ... sometimes
there is real justice.

Regards,
JS

I especially liked the experts who wouldn't use a B&W antenna under
any circumstance because it was inefficient. Even when the uses
included ALE, frequent frequency changes, and use in hostile
environments. They just gotta squeeze every last db out of a piece of
wire.

wrote:

I especially liked the experts who wouldn't use a B&W antenna under
any circumstance because it was inefficient. Even when the uses
included ALE, frequent frequency changes, and use in hostile
environments. They just gotta squeeze every last db out of a piece of
wire.


Any "expert" who doesn't consider the application is no expert at all,
and certainly not even a competent engineer. Who are these people you're
speaking of, and why do you consider them "experts"?

Roy Lewallen, W7EL

On 17 Oct, 21:56, Roy Lewallen wrote:
wrote:

I especially liked the experts who wouldn't use a B&W antenna under
any circumstance because it was inefficient. Even when the uses
included ALE, frequent frequency changes, and use in hostile
environments. They just gotta squeeze every last db out of a piece of
wire.

Any "expert" who doesn't consider the application is no expert at all,
and certainly not even a competent engineer. Who are these people you're
speaking of, and why do you consider them "experts"?

Roy Lewallen, W7EL

Interesting aproach as to what a good engineer is.
It goes without saying that the application has to be considered, even
Yogi Bear
would have come up with a better one than that and he is not an
engineer.
As an engineer myself I consider a engineer or "expert" is one that
will consider
anything unless science has definitely ruled it out and that doesn't
neccesarily
include what has been written before the question arises. Natuarally
that means
not ruling out trying ANYTHING unless one considers their minds
developed enough
that it is satisfactory to go thru the thought processes only.
On that basis this newsgroup is full of fake " experts"!
Art KB9MZ

Roy Lewallen wrote:

...
speaking of, and why do you consider them "experts"?

Roy Lewallen, W7EL

YEAH!

And besides, "Where's the beef?" ;-)

JS

On 18 Oct, 11:51, John Smith wrote:
Roy Lewallen wrote:

...

speaking of, and why do you consider them "experts"?

Roy Lewallen, W7EL

YEAH!

And besides, "Where's the beef?" ;-)

JS

Actually John my beef is that the rule for the most efficient
radiation
is that "if a radiating element is resonant and in equilibrium it can
be of any shape, size or
elevation". Yet that is ignored by the so called experts of the
amateur ranks.
I can only assume that most think themselves as being experts that
they do
not find a need to get up from the couch and try things knowing that
there
is no room for surprises over their own superior brain power.
How many would admit that :for a given polarization the best results
are NOT
at right angles or parallel to earth" ? And as somebody said "If it
was really
true it would have been invented a long time ago" as if all
discoveries have
their own time scale for discovery and time has expired for antennas
Art KB9MZ....XG
Art KB9MZ
over their thoughts.