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Old October 22nd 14, 07:05 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Mike Tomlinson" wrote in message
...
Attention.

He's a very sad, demented attention-seeking troll, as evidenced by the
Google archive of his posts dating back to 1997. What's striking about
them is that they haven't changed much in that time.


Yet again, the abuse that you seek to lay at my door originates with you.


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Old October 22nd 14, 06:12 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.



"gareth" wrote in message ...

"Wayne" wrote in message
...

If 10 watts is delivered to a short antenna, where does it go if it is not
radiated just as well as 10 watts delivered to a long antenna?


# How are you going to deliver that 10 watts? By feeding with 100 Watts?

Perhaps 100 watts to the matching system.
But, that's irrelevant to your theory.

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Old October 22nd 14, 07:11 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Wayne" wrote in message
...
Perhaps 100 watts to the matching system.
But, that's irrelevant to your theory.


So far, no-one has discussed what is NOT my theory, but established physics.


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Old October 23rd 14, 09:30 AM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"gareth" wrote in
:

So far, no-one has discussed what is NOT my theory, but established
physics.


In thread after thrad after thread, many people have done exactly that, yet
you refuse to see it, and posy yet another thread insisting on having
discovered somethign new.
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Old October 22nd 14, 05:36 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Wayne" wrote in message
...
"gareth" wrote in message ...
Try this ...


http://farside.ph.utexas.edu/teachin...es/node94.html


This is one of a series of lectures by a prof at Texas Uni.


In fact, if you go right back to the home page of
http://farside.ph.utexas.edu/teaching,
this leads to a most excellent revision of the necessary EM theories, and,
briefly
glancing thereto, the post grad stuff even exceeds my current interest and
knowledge.


I'm fairly sure now that this area is where I came across the governing
formula that I
alluded to recently in this NG when doing my own revision previously in
2005, although
the URLs and lecture node numbers have changed since then.


When I get time, I'll browse through the links.

However, back to your original assertion that your theory has short
antennas as being inefficient compared with longer antennas (I'm assuming
you are talking half wave dipoles and such).

If 10 watts is delivered to a short antenna, where does it go if it is not
radiated just as well as 10 watts delivered to a long antenna?

Dissipated as heat?
--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk



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Old October 22nd 14, 05:53 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae,as previously discussed.

On Wed, 22 Oct 2014 17:36:31 +0100, FranK Turner-Smith G3VKI wrote:

"Wayne" wrote in message
...
"gareth" wrote in message ...
Try this ...


http://farside.ph.utexas.edu/teachin...es/node94.html


This is one of a series of lectures by a prof at Texas Uni.


In fact, if you go right back to the home page of
http://farside.ph.utexas.edu/teaching,
this leads to a most excellent revision of the necessary EM theories,
and,
briefly glancing thereto, the post grad stuff even exceeds my current
interest and knowledge.


I'm fairly sure now that this area is where I came across the governing
formula that I alluded to recently in this NG when doing my own
revision previously in 2005, although the URLs and lecture node numbers
have changed since then.


When I get time, I'll browse through the links.

However, back to your original assertion that your theory has short
antennas as being inefficient compared with longer antennas (I'm
assuming you are talking half wave dipoles and such).

If 10 watts is delivered to a short antenna, where does it go if it is
not radiated just as well as 10 watts delivered to a long antenna?

Dissipated as heat?


Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left, ... I think.
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Old October 22nd 14, 06:15 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.



"Steve" wrote in message ...

On Wed, 22 Oct 2014 17:36:31 +0100, FranK Turner-Smith G3VKI wrote:

"Wayne" wrote in message
...
"gareth" wrote in message ...
Try this ...


http://farside.ph.utexas.edu/teachin...es/node94.html


This is one of a series of lectures by a prof at Texas Uni.


In fact, if you go right back to the home page of
http://farside.ph.utexas.edu/teaching,
this leads to a most excellent revision of the necessary EM theories,
and,
briefly glancing thereto, the post grad stuff even exceeds my current
interest and knowledge.


I'm fairly sure now that this area is where I came across the governing
formula that I alluded to recently in this NG when doing my own
revision previously in 2005, although the URLs and lecture node numbers
have changed since then.


When I get time, I'll browse through the links.

However, back to your original assertion that your theory has short
antennas as being inefficient compared with longer antennas (I'm
assuming you are talking half wave dipoles and such).

If 10 watts is delivered to a short antenna, where does it go if it is
not radiated just as well as 10 watts delivered to a long antenna?

Dissipated as heat?


# Probably proportionately more will be lost as heat as a very short
# antenna will be a low impedance, therefore current, driven job and I sq*R
# losses within the antenna will play their part. Apart from those
# additional losses, it should radiate all that is left, ... I think.

But I^2 R losses are not part of the theory Gareth presented.

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Old October 22nd 14, 07:11 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Wayne" wrote in message
...
But I^2 R losses are not part of the theory Gareth presented.


You may think so, but I didn't give my inside leg measurement, either, nor
did I discuss electron transport from one atom's orbit to another.


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Old October 22nd 14, 10:33 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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First recorded activity by RadioBanter: Aug 2013
Posts: 393
Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Wayne" wrote:
"Steve" wrote in message ...

On Wed, 22 Oct 2014 17:36:31 +0100, FranK Turner-Smith G3VKI wrote:

"Wayne" wrote in message
...
"gareth" wrote in message ...
Try this ...

http://farside.ph.utexas.edu/teachin...es/node94.html

This is one of a series of lectures by a prof at Texas Uni.

In fact, if you go right back to the home page of
http://farside.ph.utexas.edu/teaching,
this leads to a most excellent revision of the necessary EM theories,
and,
briefly glancing thereto, the post grad stuff even exceeds my current
interest and knowledge.

I'm fairly sure now that this area is where I came across the governing
formula that I alluded to recently in this NG when doing my own
revision previously in 2005, although the URLs and lecture node numbers
have changed since then.

When I get time, I'll browse through the links.

However, back to your original assertion that your theory has short
antennas as being inefficient compared with longer antennas (I'm
assuming you are talking half wave dipoles and such).

If 10 watts is delivered to a short antenna, where does it go if it is
not radiated just as well as 10 watts delivered to a long antenna?

Dissipated as heat?


# Probably proportionately more will be lost as heat as a very short
# antenna will be a low impedance, therefore current, driven job and I sq*R
# losses within the antenna will play their part. Apart from those
# additional losses, it should radiate all that is left, ... I think.


Actually no. The loss resistance tends to be dwarfed by the radiation
resistance, so losses in the antenna are not the problem.

The problem is matching. A small antenna has a narrow BW so you tend to
need a matching system. That is where the losses will be, plus in any
feeder.

Of course, if you only need a narrow BW and can arrange a low loss feeder
plus load the pa correctly, then pa is happy, low feeder loss, the RF gets
to the antenna.

The antenna RrRL so antenna loss is low.

RF has only one place left to go, to be radiated.




But I^2 R losses are not part of the theory Gareth presented

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Old October 22nd 14, 07:09 PM posted to rec.radio.amateur.antenna,uk.radio.amateur
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Default The inefficiency of short antennae compared to long antennae, as previously discussed.

"Steve" wrote in message
...
Probably proportionately more will be lost as heat as a very short
antenna will be a low impedance, therefore current, driven job and I sq*R
losses within the antenna will play their part. Apart from those
additional losses, it should radiate all that is left,


Some will be radiated, but in a short antenna, much less than with a
long antenna. That which is not radiated will reflect, or bounce off the
end and arrive back at the feed point.







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