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
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