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-   -   EH Antenna Revisited (https://www.radiobanter.com/antenna/1052-eh-antenna-revisited.html)

Mark Keith January 15th 04 09:52 AM

Walter Maxwell wrote:

The following is Ted Hart's response to me:

----- Original Message -----
From: Ted
To: Walter Maxwell
Cc: Bill Ronay
Sent: Tuesday, January 13, 2004 5:50 PM
Subject: EH Antenna

Hi Walter,

Every one is entitled to their opinion - but accurate test data is irrefutable.


Boy, he finally got something right...Yes, accurate tests results can
tell a lot. *IF* we get ever get to see any.
Testing a non-decoupled very small antenna that is mounted to a metal 90
foot tall tower is not accurate test data.
It is a joke of immense proportion. The BC tower in close proximity
bothers me less than this. He is not testing an E/H antenna. He is
testing a 90 ft tower and feedline, being the problem of common mode
currents on the feedline are severe. Even he admits that "rf in the
shack" can be a severe problem with these antennas. But!!! He advocates
NOT using any form of feedline decoupling. It's no wonder, being that
will effectively kill the radiation from his main radiator. Which is the
feedline and tower. Someone, maybe from "Antennex", tested an E/H
antenna fed directly from the base of the antenna, with NO feedline, and
NO tower. Needless to say, the performance was earthshaking. :( Or
maybe we should say it's non-performance....But when you have plans to
unload these buggers for appx 40k+ apiece, I guess the motivation for
*creative* testing really kicks in.
Accurate testing goes out the back window. An accurate test result will
not fit the program. The prince becomes an ugly wart infested fraug.

http://search.yahoo.com/search?x=wrt...eb-t&n=20&fl=0
http://www.google.com/search?hl=en&i...=Google+Search
for some more reading.

When he does a controlled test where the antenna is mounted on a
non-conducting tower or mast, and feeds the antenna directly at the
feedpoint using NO feedline, or at the least, a very well decoupled
feedline, then you can call it an accurate test. What he offers now is
an insult to most peoples intelligence. It's an insult to mine, and I'm
just a run of the mill dummy compared to many others on here. I suspect
most *real* broadcast engineers snicker like small school children when
they discuss the merits of the E/H antenna behind closed doors.

MK
--
http://web.wt.net/~nm5k

Richard Clark January 15th 04 10:37 AM

On Thu, 15 Jan 2004 03:52:11 -0600, Mark Keith wrote:
Boy, he finally got something right...Yes, accurate tests results can
tell a lot. *IF* we get ever get to see any.


Hi Mark,

His own data shows quite clearly that the eh antenna, 10 miles out, is
more than 30dB down from the nearby standard quarterwave it is
supposed to replace. His own data shows that at 1 mile out, the eh is
still underperforming.

There is a basic disconnect between what is claimed, and what the data
clearly shows as a burnt resistor.

More accuracy may improve the -30dB to -30.1dB but would hardly make
things any better - or any worse.

73's
Richard Clark, KB7QHC

Mark Keith January 15th 04 10:43 AM

Mark Keith wrote:
He is not testing an E/H antenna. He is
testing a 90 ft tower and feedline, being the problem of common mode
currents on the feedline are severe.


I might add, he is testing a 90 ft tower fed in a less than optimum
manner also...I could shunt feed a 90 ft tower like a normal person
would, and beat his setup any day I bet. If I top loaded the tower with
loading wires or a hat, Look out Mr. E/H ...It ain't gonna be pretty. I
wouldn't have the lossy coil in the "E/H" apparatus to contend with for
one thing. So I bet his test results of feeding the E/H ant-90 ft
tower/feedline combo, most likely are inferior to feeding a 90 ft tower
in a conventional manner, assuming equal ground losses. Note how the
comparison B/C antenna compares overall...:) So lets see...The price of
a 90 ft tower plus wire for 120 radials, or a $40k+ E/H antenna plus the
90 ft tower as support. He says you don't really need
radials...*snicker*...The E/H antenna setup will most likely be the
poorer performer of the two setups. Dunno, I know which line I'll be
in.. And I can tell you I won't have to drive to GA to pick it
up...:/ MK
--
http://web.wt.net/~nm5k

Mark Keith January 15th 04 10:50 AM

Richard Clark wrote:

On Thu, 15 Jan 2004 03:52:11 -0600, Mark Keith wrote:
Boy, he finally got something right...Yes, accurate tests results can
tell a lot. *IF* we get ever get to see any.


Hi Mark,

His own data shows quite clearly that the eh antenna, 10 miles out, is
more than 30dB down from the nearby standard quarterwave it is
supposed to replace. His own data shows that at 1 mile out, the eh is
still underperforming.

Yea, But it should be even uglier if he does away with the tower and
feedline. :( Real ugly in fact.
I doubt we will see any tests done without a metal support, or radiating
feedline. "IE: the E/H antenna tested by itself, on it's own merits".
Or at least sponsored by that bunch. I wish I could remember who tried
it without the tower and feedline...Might be in google archives...It was
so ugly, it stunk up the place. :( MK
--
http://web.wt.net/~nm5k

Walter Maxwell January 15th 04 05:02 PM

On Thu, 15 Jan 2004 04:43:59 -0600, Mark Keith wrote:

Mark Keith wrote:
He is not testing an E/H antenna. He is
testing a 90 ft tower and feedline, being the problem of common mode
currents on the feedline are severe.


Hello Mark,

Perhaps I'm not perceiving your position on the EH correctly, but from your
discussions above and in your previous post, my perception is that you believe
the EH exists and can be tested, and your problem is only with the test
procedure.

Mark, my position is that the EH does not and cannot exist in the manner Hart
specifies, because there is no way that the E and H fields can exist in time
phase--the change in each field generates the other sequentially. Hart seems to
be unaware of this fundamental fact, and also seems to be unaware that no power
can be delivered with current lagging voltage by 90 degrees unless there is an
opposite reactance to move the phase away from 90.

Since power IS delivered to the so called EH, the lagging current due to the
series inductance must simply be compensating for the capacative reactance in a
conventional shorter-than-resonant antenna, thus bringing it to resonance.

I'm saying there is no such device as an 'EH' antenna.

Walt, W2DU

Art Unwin KB9MZ January 15th 04 05:05 PM

Walter,
Since you have had a lot of success with publicly dancing on the EH grave
with this thread .could you point out any facets on the experimenation made
that could possibly be useful for further study, maybe something in the
order of radiation efficiency per unit length or something else that you may
have spotted ?
I have not got involved with the EH antenna mechanics but I would hate to
see something of interest covered purely for the sake of frivility at an
experimentors expence.
Regards
Art Unwin


"Walter Maxwell" wrote in message
...
Happy New Year to you, too, Rick.

To anyone who believes the W5QJR EH concept is valid.

I just now received a request from Rick Lutzinger, KD6ZR, asking for my

opinion
on the validity of the EH concept W5QJR touts as his invention in his

website at
www.eh-antenna.com.

I went back and reviewed the posts on this thread posted during the last

week of
September 2003. Surprisingly, I didn't find anyone who disagreed with the
concept. All I found there were disgreements with the claims for gain and
realistic claims that this antenna could not even radiate as well as a
conventional antenna. With this I agree.

The following text contains my reply to Rick:

Hi Rick,

I didn't have the opportunity to refer to Hart's fiasco until day before
yesterday. He appears to still be in the business of publishing proofs of
his limited knowledge of antenna and transmission line principles.
Unfortunately, he appears to believe he's found something new in his 'EH'
concept. On the contrary, 'his' antenna still performs as a Hertz, and his
limited knowledge has misled him believe he has something different. So
let's examine the situation.

Let's begin with a traditional resonant 1/4 wave vertical antenna over
perfect ground fed with a 50-ohm coax matched to a source delivering all

of
its available power--signifying a conjugate match. Now let's add some
inductive reactance between the coax and the antenna. There is no longer a
conjugate match, the current lags the voltage, the power factor is no

longer
100%, and the delivery of power is reduced proportionately. If we continue
to increase the inductance until the current lags voltage by 90 degrees

the
power factor is zero, because cos 90 = 0. In this case the only power
delivered by the source is that dissipated in the inherent loss of the
inductance. The reactive power contained in the inductance is reflected

back
to the source resulting in a mismatch that prevents any further delivery

of
power other than that required to supply the power dissipated in the loss
resistance of the inductance. In this condition no power will be delivered
to the antenna.

However, if a capacitor is inserted in series with the inductor having the
same but negative value of reactance as the inductor, we know that the

total
reactance now is zero, the conjugate match is restored, and the power
delivery returns to normal.

On the other hand, Hart is applying the 90-degree phase lag to a very

short
antenna, whose input impedance is capacitive. As the series inductance is
increased to where its reactance equals the negative reactance of the
antenna capacitance, we have the conventional loading and matching of an
antenna that is shorter than that of resonance.

Now if Hart is able to obtain an input to the antenna that approaches an
impedance match allowing power to be delivered into the antenna, the
capacitive reactance of his short antenna is simply compensating for the
series inductance he believes produces current that lags voltage by 90
degrees. Tain't so. He is simply feeding a traditionally matched short
Hertzian antenna. Further, voltage applied to Hart's 'EH' antenna results

in
antenna current flowing in exactly the same manner as in any antenna, and
the E and H fields are formed and are related to each other in the same
chronological manner as in any antenna. The natural laws of

electromagnetic
theory govern the field development and there is nothing anyone can do to
violate those laws developed by James Clerk Maxwell in the 1800s--they

have been
proven immutable for more than 120 years.

So how come the respondents rave about how terrific their 'EH' antennas
work? It's only because they fail to understand what is really
happening--there is no change in the chronological relationship between

the E
and H fields, as Hart has misled them to believe, they are simply using a
shortened loaded antenna in the traditional manner.

Hope you find this of value, Rick

73, Walt

PS--Please note in the References section of Reflections that an asterisk
preceding a name indicates that that reference contains erroneous and
misleading information. Now take a peek at my Reference 100. The material

in
that reference proves that that writer even then didn't didn't have a clue
concerning transmission line theory. Note also the date: March

1969--things
don't seem to change very much.

Walt Maxwell, W2DU






Walter Maxwell January 15th 04 05:38 PM

On Thu, 15 Jan 2004 17:05:01 GMT, " Art Unwin KB9MZ"
wrote:

Walter,
Since you have had a lot of success with publicly dancing on the EH grave
with this thread .could you point out any facets on the experimenation made
that could possibly be useful for further study, maybe something in the
order of radiation efficiency per unit length or something else that you may
have spotted ?
I have not got involved with the EH antenna mechanics but I would hate to
see something of interest covered purely for the sake of frivility at an
experimentors expence.
Regards
Art Unwin


"Walter Maxwell" wrote in message
.. .
Happy New Year to you, too, Rick.

To anyone who believes the W5QJR EH concept is valid.

I just now received a request from Rick Lutzinger, KD6ZR, asking for my

opinion
on the validity of the EH concept W5QJR touts as his invention in his

website at
www.eh-antenna.com.


Thanks for asking, Art, but no, I can't come up with anything new in this area.
However, if you're looking for some huffaw size grins I suggest you look at the
website shown directly above. It has several categories in a pull-to-the-right
menu for their selection. One category you'll like is 'Article', but I believe
the one with the huffaws is the 'EH Definition'.

On the other hand, the report of the measurements taken by the consulting firm
is well done and useful, but of course it's not data measured on an EH antenna,
because such an antenna doesn't exist.

I know this hasn't helped, Art, but it's the best I can do under the
circumstances.

Walt



Mark Keith January 16th 04 04:34 AM

Walter Maxwell wrote in message

I'm saying there is no such device as an 'EH' antenna.


Oh, I agree totally. I consider it no different than any other small
loaded antenna stuck on top of a tower. Well, except that it's less
efficient than many...:( But even noting that, to me, the test is a
semi-sham also. Not really due to problems from the test consultants,
but from including an obviously radiating structure and feedline with
this antenna during the test. This *requires* the same height tower
"90 ft" to be included under the antenna in order to match the results
they show. Dunno, they may have done a decent job of testing, but
someone in the office should have noted that the obviously radiating
tower and feedline would skew the results. They use no decoupling of
the feedlines. In their info, they never state that a tower is a
required section of this antenna. They consider it only a support, and
they claim it or the feedline doesn't radiate.
If I had been the test consultant, I would have demanded the antenna
be placed on a non metallic structure, and to either have the
transmitter at the feedpoint, or use a well decoupled feedline. If
they refused, I would have declined the job, being I would have
realized the results would be not a result of the small antenna, but
also include the radiating tower and feedline. And thus be pretty much
of a joke if you really want to test the antenna alone on it's own
merits. And to add insult to injury, the comparison low tech B/C tower
won the contest. I have seen notes that he states these antennas could
be roof mounted. I wonder what he will use as the *main* radiator in
this case, if there is no 90ft tower on the roof. I guess the
radiation from the feedline will have to do the job...Which could be
partly indoors, and could even be shielded by metal in places. Hot
shack RF wise too I bet. Most real world E/H tests mention this
problem. What a mess... :/ I don't see broadcast stations lining up
for this system. Only a few gullable hams...:( MK


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