[Lowfer] Ultimate LOWFER Transmitter?

[lowfer@mailman.qth.net]

G'day John,

> 
> Well, I personally suspect it depends on how you define "independent,"
> because the rough tests I have made since we first had the go-around on this
> topic lead me to believe there IS a transformation of radiation resistance.
> 

OK, let's give the description the benefit of the doubt and assume that the 
radiators actually do interact.   Of course then there is the well-known N^2 
impedance transformation of radiation resistance.  But all my knowledge of this 
also says that any losses are transformed also.   So in the first instance 
there is no gain at all as the efficiency is proportional to the ratio of 
Rrad/Rloss.   However, by splitting the currents between radiators you 
certainly would expect to get some significant benefits in terms on reduced 
current density which could be expected to help with lowering by some amount 
the aformentioned losses.  Be that as it may, this is a country mile from 
claims of 1W split between 4 radiators giving the same far field field strength 
(power density, whatever) as 4W fed into one radiator.

As far as the "eveready" analogy, I am not convinced that this analogy is an 
accurate reflection of the situation.   Painting stripes on a donkey won't make 
it a zebra :-)

I realise my scepticism can be iritating, but it is the way I am wired.  I 
believe that it is foolish to accept what you don't understand.  I would rather 
be known as someone who asks foolish questions than someone who is foolish 
enough to be afraid to ask :-)   Otherwise I might as well switch my brain off 
completely and listen to talk-back radio. My favourite fairy tale is 
the "Emperor's New Clothes" which probably explains a lot.

So, if someone can explain the how you get the 6dB apparent gain in far field 
strength in a rigorous manner (sorry, no batteries or resistors allowed) I will 
be happy to learn something I didn't understand before.   The only explanation 
I can see is that it is simply a case of reducing earth losses and is no 
different in principle to laying out an extensive earth mat as LowFers have 
been doing for years.   Of course, LowFers do not have to contend with 
*massive* antenna currents like commercial VLF installation do.  Another 
benefit might be easier impedance matching.  Also it would make engineering 
easier by reducing current density in the vicinity of the ground return due to 
skin effect.  But surely not a 6dB gain in any practical setting.

73s Steve Olney
VK2ZTO

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