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Re: Topband: Elevated Radial Efficiency - an inordinately long post

To: "William Culpepper" <>,<>, "W0UN -- John Brosnahan" <>
Subject: Re: Topband: Elevated Radial Efficiency - an inordinately long post
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Thu, 29 Nov 2007 14:43:34 -0500
List-post: <>
> I have been making this same claim for years, with a few 
> caveats,
> such as the elevated radials must not be too close to the 
> ground and
> should not be connected to an existing ground-mounted 
> system.  And
> this limitation has been confirmed with the modeling that 
> K3LC has
> done and published.

....but not a single A-B FS measurement to back up the 

> Elevated radials worked very well for me as far back as 
> pre-1990 when
> I phased two 1/4 verticals on 160 with each vertical 
> having four
> elevated radials.  75 JAs in the first contest from my CO 
> QTH (with
> K0RF operating) made me feel pretty good about the system 
> even if not
> actually proving anything.

There is equal or even more emotional data the other way. 
Ask anyone who went from a few radials to a big system how 
they "feel" about the system.

> Then K5IU's work was published that indicated even better 
> results by
> making the individual radials non-resonant (resonance is 
> where the
> slope of the reactance curve is maximum and where balanced
> (cancelling) currents are the most sensitive to variations 
> in the
> soil, etc) and the total radial system should then be 
> resonated with
> a single reactance.

Which doesn't contain a single field strength measurement. 
Not one. It is just conjecture or proposal, nothing more, 
that the reason some systems don't work so well is because 
currents are not equal. The article totally misses the 
obvious fact that the earth is in the nearfield, and so 
current balance which affects far field fields won't really 
have any major effect on near field cancellation.

No one should think that two wires distributed 30-100 feet 
apart would have induction fields cancelled at 10 feet 
distance by current balance. That's just not a reasonable or 
logical idea.

> I guess I was partly instrumental in getting W5UN to try 
> this
> approach and Dave did extensive comparison testing between 
> both an
> elevated radial antenna and a standard vertical over an 
> extensive
> ground plane and became convinced that the elevated radial 
> system,
> properly constructed, would equal a classic system.  His 
> results with
> his 4-squares with elevated radials on both 160 and 80 
> would seem to
> confirm his decision.

On the other hand in at least a dozen other clean A-B 
systems the results disagree.

Too bad in Ham radio articles or theories aren't reviewed 
and brought down to earth before being printed. Sadly we 
lack scientific method.

It is imperative that an author actually **measure** what he 
claims is changing in a direct manner. If we actually look 
at all the elevated radial articles we find they don't 
really measure FS changes at all. We have current and 
impedance measurements, but we all know (or should know) 
that the impedance of  a vertical and current distribution 
in the system can go all over the map without a tracking 
change in field strength as the system is altered.

I find it nothing short of amazing that when all these 
articles are looked at, none of the measurements actually 
measure what is proposed in the results!!!

It all winds up being emotional that the low elevated 
systems "feel good" when the only real A B measurements 
prove otherwise. I feel good about a lot of things, but it 
doesn't mean my feelings are accurate or meaningful to 
anyone but me.

73 Tom

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