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Tom Donaly wrote:

Cecil Moore wrote:

Tom Donaly wrote:
How do you know it's a "pure cosine wave," Cecil?

Because Kraus says so?

That's interesting. It means we don't need to use
NEC any more.

As I said previously, it's only a pure cosine wave for
a thin-wire dipole. NEC handles more than thin-wire
dipoles.

The coil adds a bulge to the thin-wire cosine wave but
the overall envelope is clearly visible.
--
73, Cecil http://www.qsl.net/w5dxp

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Tom Ring wrote:

Richard Clark wrote:

Hi Tom,

If the mood strikes me, I will see how much effort it takes to blow
away his "efficient" antenna. Seeing how he has no answers for its
construction, I can easily impose my own choices like an high E piano
string radiator mid loaded with a squirrel cage over a radial field of
rusting springs from a burnt-out mattress. There should be room for
improvement over that using a coat hanger with distributed loads of
barn nails over the roof of a 1948 Hudson.

73's
Richard Clark, KB7QHC


I would prefer a radiator made from half inch PVC filled with a dilute
sodium chloride solution. If you put a valve at the bottom, it's a snap
to adjust resonance.

tom
K0TAR

Have you tried beer?
73,
Tom Donaly, KA6RUH

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I'd guess that Reg would use wine.

Cheers,
another of the Toms

(Now if W8JI will just add something to this subthread, we'll have four
of us in a row...)

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Tom Donaly wrote:

I would prefer a radiator made from half inch PVC filled with a dilute
sodium chloride solution. If you put a valve at the bottom, it's a
snap to adjust resonance.

tom
K0TAR


Have you tried beer?
73,
Tom Donaly, KA6RUH

What!!?? That would be a waste of beer. Well, unless it was Budweiser.

tom
K0TAR

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Tom Ring wrote:

Tom Donaly wrote:

I would prefer a radiator made from half inch PVC filled with a
dilute sodium chloride solution. If you put a valve at the bottom,
it's a snap to adjust resonance.

tom
K0TAR



Have you tried beer?
73,
Tom Donaly, KA6RUH


What!!?? That would be a waste of beer. Well, unless it was Budweiser.

tom
K0TAR

What is the bulk conductivity of 'Bud'? How does the bulk conductivity
differ from other Beers? [I am a non drinker]

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1
"Tom Ring" wrote in message
.. .
Tom Donaly wrote:

I would prefer a radiator made from half inch PVC filled with a dilute
sodium chloride solution. If you put a valve at the bottom, it's a snap
to adjust resonance.

tom
K0TAR


Have you tried beer?
73,
Tom Donaly, KA6RUH

What!!?? That would be a waste of beer. Well, unless it was Budweiser.

tom
K0TAR

finally someone said something that makes sense in this thread... but no one
has addressed my original question directly... but i guess that is par for
the course in here when this group gets wound up, everyone goes off on their
own little tangent and starts attacking each other.

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Tom, K7ITM wrote:
"(Now if W8JI will just add something to this subthread, we`ll have four
of us in a row---)"

Like the beat, beat, beat of a tom-tom--- No, that`s the wrong song.
It`s the one Merv Griffen sang with the Freddy Martin Orchestra:
"I`ve got a loverly bunch of coconuts. There they are all standing in a
row. Large ones, small ones, some as big as your `ead, Give `em a twist,
a flick of your wrist, that`s wot the showman said."

Best regards, Richard Harrison, KB5WZI

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Dave wrote:
finally someone said something that makes sense in this thread... but no one
has addressed my original question directly... but i guess that is par for
the course in here when this group gets wound up, everyone goes off on their
own little tangent and starts attacking each other.

I tried to, but I see it did no good at all.

I have a Force 12 80 and 40 meter linear loaded Yagi.

The Q of the loading sections are terrible. They are thin aluminum wire
of some sort of alloy that makes them hard.

For the typical reactances produced by that loading system Q (reactance
over ESR) is well in the sub-100 range.

That's why you can take even a fairly poor loading coil, replace the
linear loading, and have the same perfromance. Or you can make a good
coil, like airdux or BW stock with number 12-14 wire, and make the
antenna work better (IF you can keep it from falling apart in the
wind).

The results of linear loading depends on where the linear loading is
installed and how it is constructed, but the general rule is if you
take the very same size and material conductors and wind a coil it will
work better.

Now I suppose we can talk about UHF antennas, 1/2 inch copper tubing
stubs, Cecil's imaginary reflected waves, quote Harrison's book
collection.....but that's how the Force 12 linear loaded 80 and 40
meter antennas I have work.

That's why they are laying in a pile with waddled out holes near the
rivets and all that lossy linear loading wire wrapped up in a ball,
waiting the be rebuilt into good antennas.

73 Tom

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Dave wrote:

What!!?? That would be a waste of beer. Well, unless it was Budweiser.

tom
K0TAR


What is the bulk conductivity of 'Bud'? How does the bulk conductivity
differ from other Beers? [I am a non drinker]


Well, you can't waste Bud. For those that appreciate real beers and
lagers, Budweiser is universally shunned. One batch at the factory, add
preservatives, flavor enhancers, artificial flavorings, and voila! You
have 10 different kinds of Bud. Or so I've heard. ;)

I'm not sure about the conductivity. It might be worth buying a single
to test.

tom
K0TAR

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wrote:
Now I suppose we can talk about ...
Cecil's imaginary reflected waves, ...

Sorry, Tom, I cannot take credit for reflected waves on standing
wave antennas. That you didn't realize that you were dealing with
a standing wave antena is part of your problem.

Kraus: "A sinusoidal current distribution may be regarded as the standing
wave produced by two uniform (unattenuated) traveling waves of equal
amplitude moving in opposite directions along the antenna."

Balanis: "The sinusoidal current distribution of long open-ended linear
antennas is a standing wave constructed by two waves of equal amplitude
and 180 degree phase difference at the open-end traveling in opposite
directions along its length."

Balanis: "The current and voltage distributions on open-ended wire
antennas are similar to the standing wave patterns on open-ended
transmission lines."

Balanis: "Standing wave antennas, such as the dipole, can be analyzed
as traveling wave antennas with waves propagating in opposite directions
(forward and backward) and represented by traveling wave currents ..."
--
73, Cecil http://www.qsl.net/w5dxp