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#1
 external usenet poster First recorded activity by RadioBanter: Sep 2012 Posts: 1,382
The inefficiency of short antennae compared to long antennae, as previously discussed.

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.

#2
 external usenet poster First recorded activity by RadioBanter: May 2011 Posts: 539
The inefficiency of short antennae compared to long antennae,as previously discussed.

On 10/22/2014 5:13 AM, gareth wrote:
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.

Obviously, none of this is new. It states in the article that the short
antenna is inefficient due to the wire (ohmic) resistance swamping the
wire resistance in your statement that short antennas are inefficient,
which is why people jumped on that statement.

If you include wire resistance, yes, a short dipole is less efficient
that a full-sized dipole (if you can manage to get the power into it,
which is a different problem). Note that a short antenna, properly
constructed with, say, 4-inch copper pipe will be just about as
efficient as one with #12 copper wire.

Try it, please. Make the measurements. Record what you get and let us
know. We are hungry for additional knowledge.

#3
 external usenet poster First recorded activity by RadioBanter: Jul 2006 Posts: 409
The inefficiency of short antennae compared to long antennae, as previously discussed.

"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?

#4
 external usenet poster First recorded activity by RadioBanter: Sep 2012 Posts: 1,382
The inefficiency of short antennae compared to long antennae, as previously discussed.

"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?

#5
 external usenet poster First recorded activity by RadioBanter: May 2011 Posts: 539
The inefficiency of short antennae compared to long antennae,as previously discussed.

On 10/22/2014 10:05 AM, gareth wrote:
"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?

Oops! Is that part of the problem? You never said matching was involved.

Tell us your requirements. Using real wire? What diameter? What
material? What length? Is feeding the antenna part of the problem?

What the hell are you seeking?

#6
 external usenet poster First recorded activity by RadioBanter: Nov 2012 Posts: 989
The inefficiency of short antennae compared to long antennae,as previously discussed.

On 10/22/2014 11:15 AM, John S wrote:

What the hell are you seeking?

Drama

--

Rick
#7
 external usenet poster First recorded activity by RadioBanter: Sep 2012 Posts: 1,382
The inefficiency of short antennae compared to long antennae, as previously discussed.

"gareth" wrote in message
...

I despair that those who are motivated to shout out childish remarks
continue to do so, even in the face of an informative post.

#8
 external usenet poster First recorded activity by RadioBanter: Nov 2007 Posts: 568
The inefficiency of short antennae compared to long antennae, as previously discussed.

In message , rickman
writes
On 10/22/2014 11:15 AM, John S wrote:

What the hell are you seeking?

Drama

And, of course, confrontation.
--
Ian
#9
 external usenet poster First recorded activity by RadioBanter: Sep 2012 Posts: 1,382
The inefficiency of short antennae compared to long antennae, as previously discussed.

"Ian Jackson" wrote in message
...
In message , rickman writes
On 10/22/2014 11:15 AM, John S wrote:

What the hell are you seeking?

Drama

And, of course, confrontation.

Untrue.

The confrontation is sought only by those who seek to respond
in a tendentious and abusive manner, such as John S and rickman
above.

#10
 external usenet poster First recorded activity by RadioBanter: Sep 2006 Posts: 137
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.

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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