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Date: Thu, 04 Jul 2013 14:37:18 +0200
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From: "Roelof Bakker" <roelof@ndb.demon.nl>
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Subject: Re: LF: VK1OD's analysis of the MiniWhip antenna
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Status: O

Hello Stefan,

I have been reading VK1OD's article with great interest.
It is a pity that he has not discussed the antenna with yours truly.
This should have avoided a number of inaccuracies.

I have had quite a few email exchanges with a number of experts.
Some state that the antenna can't work, others said that it works, but  
that I did not understand how it works.
Which was true!

The antenna has evolved completely by experimental work with the goal to  
find an antenna that will work on LF and features immunity to in house  
local noise. Which goal has been achieved.

To understand how it works requires a bit of up side down thinking  
(literally!)
The antenna emulates a monopole, however what we consider to be the  
antenna element, it is not.

This applies also to the classic active whip, at least on LW and MW.
In fact, the antenna element should be considered as an artificial ground  
and that is the reason that e.g. a 1 meter long whip can be replaced by a  
piece of copper clad PCB with about the same capacitance.

There is no question that this concept works. I received NDB IPA-280 from  
Easter Island in the Pacific on it.
And no weak trace screen watching whatsoever, but aural copy of the ID in  
morse code.

It should be nice if all members of the amateur community were well off  
and could afford unlimited real estate.
In that case we all should be using beverage farms for reception and  
spending a bit more time in the great outdoors to keep things up and  
running.

However the vast majority will have to cope with limited resources, being  
lack of real estate, lack of finances or both. This is where a bit of  
ingenuity comes into play and the fun starts.

It is truly amazing what ideas have been put to work to overcome  
unsurmountable limitations. One excellent example is the ongoing  
development of weak signal software, which has made LF work possible for  
many more people than just the happy few!

Best regards,
Roelof Bakker, pa0rdt