Some time ago I mentioned how inefficient Yagi design
antennas were thinking more in the way of how little of
the radiation used got to its required direction.
At that time people said the antenna was efficient though
they wanted to talk about
actual radiation efficiency and the sniping began
..Nobody but nobody came back with the radiation
efficiency of a Yagi as they saw the question, they
just wanted to throw stones.Imagine that antennas
was not what the experts wanted to talk about and
the newsgroup took a turn for the worst
So I join in with the thoughts of radiation efficiency
of a yagi unless you prefere to give up this antenna
newsgroup. But before you scream out and throw
stones again I will referr to efficiency as most of the
members of this group what's left of them think of the term.
So let's look at that if that is what you preferr..

The basic small yagi has three elements one driven,
one a reflector and one a director yet only one
element has a truly resistive impedance whereas
the other two do not. Since two elements out of the
three are producing reactive impedances and wherein
the reactive portions of impedance is pure waste
pray tell me how one can consider a yagi as efficient?
And please, please don't waste time on "I don't understand"
otherwise everything drops down to the subject of spark noise
which was really decided by hams a long while ago.
On the other side of the coin, if the reactive portion of an
impedance is not waste then why is LCR
type mesh circuitry only revolve around lumped circuitry?
HINT add up the power emminating from each element
P =I sq times real resistance for those who are just followers.

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!

art wrote:
snip

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Actually Art, you are already the master of misunderstanding.

tom
K0TAR

art wrote:

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Interesting, but you cannot argue with decibels, and the yagi is more
efficient that a dipole without reflector and director, at least at
capturing signal.

However, while I can picture the reflector acting as a mirror (and to
some extent, this can be "proven", make the reflector a sheet and see
how much signal is radiated to the other side, away from the driven element.

But, that darn director has always bothered me, I see it acting more as
a "magnifying glass to rf" than absorbing the signal and re-radiating it
to the de, or absorbing the signal and coupling it to the de via
magnetic or capactive means... one more bit of a puzzle which gives me
visions of the ether (which some say is caused by evil spirits and/or
the drugs I did in college (I don't think the beer hurt anything!))

But, with his calculator in hand, I know cecil will take this head on...

JS

Tom Ring wrote:
art wrote:
snip

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Actually Art, you are already the master of misunderstanding.

tom
K0TAR
See Tom you had nothing of value to say about antennas or the question
at hand
I think you would be better conversing with members of this group who
are intent on disruption and stop questions on antennas. What goes
around comes around so I will not answer in kind. If you want to stick
with the idea that a yagi is the next thing to sliced bread then be my
guest Better still study up on the code so you can join friends.

art wrote:

Tom Ring wrote:

art wrote:
snip

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Actually Art, you are already the master of misunderstanding.

tom
K0TAR

See Tom you had nothing of value to say about antennas or the question
at hand
I think you would be better conversing with members of this group who
are intent on disruption and stop questions on antennas. What goes
around comes around so I will not answer in kind. If you want to stick
with the idea that a yagi is the next thing to sliced bread then be my
guest Better still study up on the code so you can join friends.


Actually Art, you never listen to reasonable arguments, so I didn't
offer one.

tom
K0TAR

art wrote:

Tom Ring wrote:

art wrote:
snip

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Actually Art, you are already the master of misunderstanding.

tom
K0TAR

See Tom you had nothing of value to say about antennas or the question
at hand
I think you would be better conversing with members of this group who
are intent on disruption and stop questions on antennas. What goes
around comes around so I will not answer in kind. If you want to stick
with the idea that a yagi is the next thing to sliced bread then be my
guest Better still study up on the code so you can join friends.


And to continue the theme -

Actually Art, yagis are usually better than 95% efficient.

tom
K0TAR

"art" wrote in message
ups.com...
Some time ago I mentioned how inefficient Yagi design
antennas were thinking more in the way of how little of
the radiation used got to its required direction.
At that time people said the antenna was efficient though
they wanted to talk about
actual radiation efficiency and the sniping began
.Nobody but nobody came back with the radiation
efficiency of a Yagi as they saw the question, they
just wanted to throw stones.Imagine that antennas
was not what the experts wanted to talk about and
the newsgroup took a turn for the worst
So I join in with the thoughts of radiation efficiency
of a yagi unless you prefere to give up this antenna
newsgroup. But before you scream out and throw
stones again I will referr to efficiency as most of the
members of this group what's left of them think of the term.
So let's look at that if that is what you preferr..

The basic small yagi has three elements one driven,
one a reflector and one a director yet only one
element has a truly resistive impedance whereas
the other two do not. Since two elements out of the
three are producing reactive impedances and wherein
the reactive portions of impedance is pure waste
pray tell me how one can consider a yagi as efficient?
And please, please don't waste time on "I don't understand"
otherwise everything drops down to the subject of spark noise
which was really decided by hams a long while ago.
On the other side of the coin, if the reactive portion of an
impedance is not waste then why is LCR
type mesh circuitry only revolve around lumped circuitry?
HINT add up the power emminating from each element
P =I sq times real resistance for those who are just followers.

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Hi Art

OK, I dont understand. Perhaps I could begin to understand if I was
given the definition of efficiency we are using in this discussion. How do
you define efficiency?

Jerry

art wrote:

See Tom you had nothing of value to say about antennas or the question
at hand
I think you would be better conversing with members of this group who
are intent on disruption and stop questions on antennas. What goes
around comes around so I will not answer in kind. If you want to stick
with the idea that a yagi is the next thing to sliced bread then be my
guest Better still study up on the code so you can join friends.


And, actually Art, and most important, you seem to have no comprehension
about what is possible to realize with a yagi that is about a half
wavelength. What you want to do takes yagis that are 10, 20 or more
wavelengths. And very high above the ground.

Reality is a nasty thing.

tom
K0TAR

John Smith wrote:
art wrote:

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Interesting, but you cannot argue with decibels, and the yagi is more
efficient that a dipole without reflector and director, at least at
capturing signal.

So the increase in reactive impedances radiation efficiency goes up?


However, while I can picture the reflector acting as a mirror (and to
some extent, this can be "proven", make the reflector a sheet and see
how much signal is radiated to the other side, away from the driven element.hat energy d it

Oh come on John, Llewellyn states the rear adds to forward radiation
and you come along with similar junk. A vector to the rear where there
is an detuned element which some how
over turns the idea of energy can't be created or destroyed ? I suppose
Roy will come up with some trash that because the reflector is reactive
it overcomes the vector that created it!



But, that darn director has always bothered me, I see it acting more as
a "magnifying glass to rf" than absorbing the signal and re-radiating it


Come on John if it is detuned from the frequency of use it can;'t be
reradiating everything
remember the hint I gave in the posting


to the de, or absorbing the signal and coupling it to the de via
magnetic or capactive means...
Oh John you have done it again if you are going to revolve
your position around coupling then losses will mount up
even more. It really isnt a puzzle unless you listen to
comments from experts who only read about Yagi's
and shut everything else out or are just looking for an
opportunity to snipe or emmulate snow code.

one more bit of a puzzle which gives me
visions of the ether (which some say is caused by evil spirits and/or
the drugs I did in college (I don't think the beer hurt anything!))

But, with his calculator in hand, I know cecil will take this head on...

I thought ether was something that did not posses its own energy
support
only a mediam for energy to pass thru, but we could change the
subject to that I suppose


JS

John Smith wrote:
art wrote:

There again maybe it is best that you be honest and say
you don't understand! Better that than join those who have
nothing to say about antennas!


Interesting, but you cannot argue with decibels, and the yagi is more
efficient that a dipole without reflector and director, at least at
capturing signal.

So the increase in reactive impedances radiation efficiency goes up?


However, while I can picture the reflector acting as a mirror (and to
some extent, this can be "proven", make the reflector a sheet and see
how much signal is radiated to the other side, away from the driven element.hat energy d it

Oh come on John, Llewellyn states the rear adds to forward radiation
and you come along with similar junk. A vector to the rear where there
is an detuned element which some how
over turns the idea of energy can't be created or destroyed ? I suppose
Roy will come up with some trash that because the reflector is reactive
it overcomes the vector that created it!



But, that darn director has always bothered me, I see it acting more as
a "magnifying glass to rf" than absorbing the signal and re-radiating it


Come on John if it is detuned from the frequency of use it can;'t be
reradiating everything
remember the hint I gave in the posting


to the de, or absorbing the signal and coupling it to the de via
magnetic or capactive means...
Oh John you have done it again if you are going to revolve
your position around coupling then losses will mount up
even more. It really isnt a puzzle unless you listen to
comments from experts who only read about Yagi's
and shut everything else out or are just looking for an
opportunity to snipe or emmulate snow code.

one more bit of a puzzle which gives me
visions of the ether (which some say is caused by evil spirits and/or
the drugs I did in college (I don't think the beer hurt anything!))

But, with his calculator in hand, I know cecil will take this head on...

I thought ether was something that did not posses its own energy
support
only a mediam for energy to pass thru, but we could change the
subject to that I suppose


JS