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Old April 2nd 06, 07:18 PM posted to rec.radio.amateur.antenna
Dan Andersson
 
Posts: n/a
Default What is an EH antenna

Richard Clark wrote:

Hi Jimmie,

I hope you appreciate the mix of confusion, theory, hope, and despair
that follows this subject. :-)

On Sun, 02 Apr 2006 16:09:37 +0100, Dan Andersson
wrote:

So, the subject is still taboo.


Well, that's a new way to approach the subject, tie it to sex.

was in the RSGB Radcom


Vanity publishing is not science.

Professional tests? Wasn't there a proper evaluation done on a commercial
EH for a radiostation a couple years back?


For what it was worth: -10dB at best, and a signal diving into the
noise floor 20 miles away for an AM band signal. The upshot of it
all, was if you couldn't see it, you couldn't hear it. Same fate as
the common rubber duckie antenna.

The EH lost because of the price,


An old oil drum with a beach umbrella cost that much? This goes
against the their noted claims of it being cheaper than a standard
design.

not because of performance. The EH results gave a S/N improvement of 5 to
7 dB, which dramatically improved the telemetry systems functionality. As
this was a commercial evaluation, no data where released. d


Soounds like a combination of the OJ Simpson defense and the Kennedy
assassination theory.

When he presented the noise bridge,
there where no problems at all as I remember it.


A noise bridge is to signal performance as a gas gauge is to
horsepower.

The best tests of the EH so far have been on VHF and without any coax
connected to the EH.


You can work the space shuttle without coax connected to a rubber duck
antenna either. Why build an eh when you already have a rubber
duckie?

BTW! I'm quite sure many of us stumble on the EH's daily nowadays as a
common use of the EH is for RFID equipment.


You have a proper reference for that of course. The reigning
crack-pot-king insists they are fractals.

73's
Richard Clark, KB7QHC




Richard,

One of the licensees are an Israeli supplier of RFID systems. You need to
check on the www.e-antenna.com for any references to them.

The rubber duck antennas are mostly to sensitive to metallic objects in the
proximity. There was actually good reasons to choose the EH but as the cost
for a helical was counted in cents, a multi dollar cost for an EH
replacement was a definitively showstopper.

The claim to be cheap could probably be true for a commercial AM transmitter
as you need a significant lesser amount of property to house it.

As I was writing about VHF antennas, the amount of property needed is not
really anything to do with cost...

The other comments from you Richard, went into the bin as just stupid
remarks and not really productive - merely as it tends to be on Usenet...

I've seen to much weirdness in the debate surrounding the EH's but I have to
admit that the CFA is something I'd rather avoid spending time on...

Unfortunately, the debate in this matter tends to go religious and that
excludes any real possibility to neither debunk nor confirm the EH. Pity.


So Jimmy,

By firing of questions about EH's you will really stir up a hornets nest...

Cheers

Dan / M0DFI