TopBand: Gads, weird science again

[w8ji.tom]

Hi Yuri,

> Yes, it can be measured by using ferrite rod antennas (might be hard to
do
> with weak signals). The wave angle is more likely to be the dominant
factor,
> due to polarity being "fuzzied" and "wandering around" by the wave going
> through the media after appreciable distance. 

That is not true Yuri. Polarity is no more "fuzzied" or "wandering around"
than wave angle is. 

The earth and everything around the rod antenna combines to modify the
pattern of the ferrite rod antenna. You really would only be measuring the
effects of earth and everything around the rod antenna on the arriving
signal, the lower you placed the rod the higher the wave angle and the more
vertical the polarity would appear regardless of what the optimum wave
angle really was.

Short of having a 2000 foot electrically transparent tower or balloon
supported system, you couldn't measure a thing that would tell you the true
optimum wave angle. Read my response where I draw an analogy to 20 meter
antennas at 8 feet height. 

> Well, at VE1ZZ QTH I used as vertical 4 square of Inv L's, longer than
quarter
> wave, each with over 100 radials (using hardline coaxes and steel guy
wires as
> radials) under each, sitting on the hill next to salt water. The inverted
Vee
> was at 60 ft tower. In this case 4square would produce lower angles than
one
> vertical alone. 

There is precious little difference in wave angle between the four square
and a single vertical element. Model it and look at it, using typical
phasing. And again, VE1ZZ's QTH is hardly representative of anyone else's
QTH, with a sharp steep rolloff to the ocean. 

His antenna is what,  200 feet or more above the ocean with a sharp drop
off to the ocean? That's hardly equal to a 50 foot tall dipole inland.
Being half-way to Europe with only a steep drop to saltwater is hardly a
typical situation.   

>Again, I was able to work Euros about an hour earlier on InvV
> than on 4 Square. In my mind there is no question that the effect was
> primarily due to the angle. Polarization "wandering" usually is of short
> duration (like around minute) while angle "thing" lasts up to about an
hour.

Yet when I heard you on at VE1ZZ later, you were puzzled when people kept
telling you the  4 square was better. Who knows what happens one time on
one day, especially with twisted wires in an unfamiliar station. It takes
day after day comparisons to reach any conclusion about trends.

> It is possible with ferrite stick antennas (it is done with Fox Hunt, or
RDF
> sport too.)

No, that is still incorrect.
 
>    BTW Jack keeps that "lousy" InVee up, few times he found it handy when
> 4square couldn't cut it.

"Few times" is the key word. A "few times" I find one antenna better than
another just because one antenna happens to be in a short deep fade.
Sometimes it happens when comparing one vertical to another. If I had a V a
few hundred feet above salt water, I'd expect it to be better than my
dipole at 260 ft over Georgia dirt. 

I'm not disputing the fact at any given moment you might pop to a different
antenna and NOT have that antenna in a fade, it is the claims we can sort
out the reason why this happens and put hard numbers on polarity and wave
angle I dispute. VE1ZZ is also not a good comparison to inland stations, no
more than claiming W1BB's dipole was 80-90 feet tall when he worked Europe
from the water tower.

It is absolutely impossible to measure optimum wave angle at any single
height unless you factor out the effects of earth on the antenna pattern,
especially near earth with horizontal polarity, because the effect of earth
modifies what is measured and the pattern of the antenna used to make the
measurements.

Measuring propagation near earth is like measuring light color through a
gas, you only see the filtered results. I wish it were otherwise.

73 Tom

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