On Wed, 01 Oct 2003 08:02:59 GMT, "stefano" wrote:
Hi Richard,
ok one small step better, now.. :-)
The cylinders/radiators are completely insulated from his tower support.
Hi Stefano,
We all realize that you are not adept at the science of antenna design
so we expect you do not understand these issues.
Then the top supporting piece of the tower is insulated from the bottom one.
This is, of course, immaterial.
I imagine you could say the capacitive coupling between the
cylinders/radiators and the under metallic structures , can be enough to
allow some rf currents flow on them.
This is in fact what happens. The physics will not allow prevent it.
But this , for me, is NOT enough to call the antenna ..a top hat one.Is not.
Again, you say this because of your inexperience in the matter. Top
Hats are part and parcel to antenna design, not for people to wear.
Please understand that it is not an article of clothing, it is a
working element of many antennas and necessary for small ones to
become partially efficient.
Yes the consultant engineer noted about some influences due to the local
power line and, may be, to the 1/4 spaced reference tower.
In fact the EH showed some directivity.
This, do not worry, can be further investigate in the near future .
Further investigation is not necessary, all the data is present. If
you do not trust this data, then you should not be here.
Since we
know very well , from many our previous measures , the antenna can be equal
to a standard 1/4 tower vertical
The point of the test was to prove this. The test proved it is not.
The eh/tower/top-hat are 66% LESS efficient and the test proves this.
, we are very confident all can be
demonstrated in the near future when Ted will sell the first antennas.
Why didn't he sell one to the test station?
He's collected some orders already, so we will see soon.
But he has not sold his first one - BIG difference (like 66% LESS
efficient).
The blue curve on the charts is the 1/4 tower standard with 120 radials.
They are the wrong ones.
The consultant proved this antenna is perfectely FCC compliant as class B.
Because it meets the MINIMUM requirement of a LOW EFFICIENT design.
The antenna in the background of the picture is BETTER! The data
proves it.
We are speaking of an antenna considered as a standard.
Well the small red dots plotted around this blue curve are the EH ones.I
think is evident how close is (on the average) to it.
The standard you speak of is the wrong one. The FCC describes the
ground around Eatonton as having 4mS of conductivity. The antenna
curve used is 2mS of conductivity. This means 3dB LOSS.
Is my opinion that any system you can model being 90 feet high with NO
GROUND and with NO RADIALS can not be as efficient as the EH antenna under
test.
I am glad to see you agree that ANY antenna is as good as eh antenna.
No one needs eh antenna.
Note I said 90 feet high because I know you are sure that ALL the system is
radiating....but is not.
73's and best regards
Steve Ik5IIR
Hi Stefano,
You are relatively untutored in the science of antennas, that is why
you come here for advice. We all recognize that the eh antenna alone
is a very poor one and that it needs other elements, such as a 90 foot
tower and top-hat to achieve 33% efficiency of standard antenna shown
in background. The data proves this. You need only look at the
numbers that you have difficulty with.
Let's look at several so that you can understand how poor the eh
antenna is:
point# Std Field eh Field eh Loss
1 310 275 -1.04dB
2 295 220 -2.55dB
3 66 43 -3.72dB
4 46 30 -3.71dB
5 36 24 -3.52dB
6 23 17.5 -2.37dB
7 20.1 12 -4.48dB
8 19.9 11.6 -4.69dB
As you can plainly see from the data taken, the further you go out the
worse the efficiency becomes. Point 8 is less than 3kM away and
compared to the antenna in the background:
the eh/tower/top-hat has an efficiency of 58%.
The antenna in the background has an efficiency of 100%
There are many charts, and on EVERY one there is in the last column a
description of eh efficiency and if we choose the efficiency of the
antenna at the last point or at least 10 miles (where the audience
is):
035° 2mS 67%
075° 2mS 61%
135° 3mS 65%
210° 1mS 81%
260° 0.1mS 120%
320° 1.5mS 59%
It is evident that the eh/tower/top-hat was compared to 5 different
FCC antenna curves! NONE of them were for the FCC mapped value of 4mS
ground conductivity even when Eatonton is in the middle of that
region. We can also see that there is a 29.5dB variation between
those curves! Where is the greatest variation? Pointed directly at
the nearby radiator of the standard antenna. If that antenna, and
power lines, and tower, and top-hat were gone (use a wood mast with
nylon rope and a choked transmission line); then the eh would be dead
on arrival.
The data simply says the eh is a dog.
73's
Richard Clark, KB7QHC
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