"Reg Edwards" wrote in message
...
Roy, you are a pessimist.

Roy has a point.The article was very sparse with real fact, but rich in
speculation and totally void of specifications.
They were working on a 3 ft piece of this conductor for testing - so they
didn't have their eye on making a dipole for 160m - more than likely. :-)

Does this mean that the resistance per ft for nanotubes is 1/10th that of
copper?


Rather than "nanotubes" I would assume that they are talking about some
kind of "room temperature" super conductor.



Ed

1/10 ohms of copper certainly is not a superconductor, however, it is a MUCH
superior conductor!

Regards,
John

You know--this almost sounds like science fiction to me--if I had not
already been witness to truth being stranger than fiction--I'd think, "FAT
CHANCE!"
However, my audio is fine, it does not need any improvement to please me
more... BUT, antennas are a different story, it will revolutionize them!!!
And, how about PC boards, your traces would only need to be 1/10 the size!
And, how about semi-conductors themselves???
etc, etc, etc....
The future only gets better and brighter....

Regards,
John

On Wed, 27 Apr 2005 18:08:52 -0700, I.Care wrote:

NASA is funding a new type of wire that can transmit power 10 times
better than normal wire. Will this make a difference in Audio?

Only to those who sincerely wish while closing their eyes very, very
hard.

http://www.wired.com/news/space/0,2697,67350,00.html

An OK general announcement that is rather a hodge-podge of facts and
characteristics. Wired is hardly a cutting edge science venue. One
particular howler is the construction of a "quantum wire" from a
wrapping of several many nanotubes. This is a contradiction in terms.
The nanotubes are already quantum wires, in fact they are called 1D
forms.

Being "quantum" anything, they are consistent in exhibiting non-linear
electrical/physical properties. Ohms law (being yet another model
that those who lambaste models would be surprised to learn) fails to
uniquely express what resistance this wire would exhibit (Onsager's
Relation drawn as a Landauer curve). However in conductance
measurements, carbon nanotubes will support a billion Amperes per
square centimeter.

However, no carbon nanotube is a square centimeter, being more often
10s of nanometers in diameter, they are still not square (area)
defined (that "quantum" thingy again). The problem of the article is
that it is mixing the bulk carbon nanotube properties with the quantum
carbon nanotube properties - not at all the same thing. This is why
the conductance of a quantum nanotube wire in billions of Amperes
plunges to a rather more mundane 1/10th the resistance of copper for a
nanotube bundle.

The quantum properties quite rightly dismiss any notion of skin
effect, current travels inside the tube. In fact, it also distorts
the shape of the tube like a snake swallowing a golf ball. Even more
interesting is that current will flow in the opposite direction of the
applied EMF if there is a sufficient heat differential between the
ends (it doesn't take much heat because carbon nanotubes are
exceptionally good heat conductors). Firstly, getting current into a
carbon nanotube is not a pretty thing as they exhibit what is called
"non-reproducible behavior" by their nature of having a great variety
of conduction configurations that all arise out of their binding to a
contact material. For nano-conductors, contacts dominate everything.

All-in-all, the introduction of a new technology is frequently
confused as a better version of an old technology - something like
saying facsimile would replace the newspaper - or that the utilities
would pay us to use nuclear power. All the "forecasts" mentioned in
this article rank right up there with these world class pipe dreams.

73's
Richard Clark, KB7QHC

Richard Clark wrote:
. . .
All-in-all, the introduction of a new technology is frequently
confused as a better version of an old technology - something like
saying facsimile would replace the newspaper - or that the utilities
would pay us to use nuclear power. All the "forecasts" mentioned in
this article rank right up there with these world class pipe dreams.

On the other hand, sometimes the assumption that the new technology will
simply replace the old falls staggeringly short. The total market for
transistors was initially seen as being the same as for tubes -- replace
each tube with a transistor, and that's it. Hardly worth developing the
technology to overcome the gnarly manufacturing problems (e.g., extreme
purity requirement of the base material). No one foresaw the integrated
circuit, making it practical to put the equivalent of hundreds of
transistors in a pocket calculator, wris****ch, or even an electric
iron. The transistor made possible a whole new technology with
applications which were altogether impossible and therefore unimaginable
with tubes. But the best that the soothsayers can ever seemingly do is
to extrapolate from what we've got right now. Maybe the nanotubes won't
end up being simply a replacement for wires, but the basis for a whole
new technology we can't now conceive.

And maybe they won't. Every entrepreneur does his best to convince
investors that his invention will be the next integrated circuit or his
garage company the next Microsoft. But the odds are sure against it.

Roy Lewallen, W7EL

On Thu, 28 Apr 2005 02:58:43 -0700, Roy Lewallen
wrote:

Every entrepreneur does his best to convince
investors that his invention will be the next integrated circuit or his
garage company the next Microsoft. But the odds are sure against it.

Been There [many times]
Failed at That [in direct proportion]

"I.Care" bravely wrote to "All" (27 Apr 05 18:08:52)
--- on the heady topic of "All wire the Same? Maybe not in future."

I. From: I.Care
I. Xref: aeinews rec.radio.amateur.antenna:29266

I. NASA is funding a new type of wire that can transmit power 10 times
I. better than normal wire. Will this make a difference in Audio?


Will it transmit power better than silver wire?

A*s*i*m*o*v

.... I cut it three times already and it's still too short!

I.Care wrote:

NASA is funding a new type of wire that can transmit power 10 times
better than normal wire. Will this make a difference in Audio?

http://www.wired.com/news/space/0,2697,67350,00.html

I'm reminded of the hype over bubble memories some years ago. They were
going to be the ultimate memory, where are they now?

--

Peter

Wired Mag. is far from being all "hype", it is on the cutting edge of making
the public aware. a practice which the news media has abandoned.

Such as the following article:

http://wired-vig.wired.com/wired/arc...9/diamond.html

However, since the great majority of people do not realize what this means,
they still purchase diamonds at ridiculous prices. I wish they would stop,
as hard as diamonds are, I'd like to pave my driveway with them!!!



Regards,

John