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  #21  
Old February 12th 04, 10:04 PM
Benoit Morrissette
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On Thu, 12 Feb 2004 08:25:41 -0500, "BenignVanilla"
wrote:


"Benoit Morrissette" wrote in message
.. .
snip
A few years ago, i worked in a hi-fi store and we had a very special

loudspeaker
wire ( i.e. very costly ) from France. It was said that the crystaline
structure of the "oxygen-free copper" acted like a diode and there was a
specific way to hook it up between the amplifier and the speakers.

Connected
the right way, the sound was gorgeous and the other way, the sound was
horrible... ( i have tried this with other wires and it work most of the
times).

My point is: the signal in the wire is AC, ok? There should be NO

difference
OK? But there is one, i swear it... No electromagnetic theory can

explain that
observation so far. I believe we are due for a new electromagnetic theory
(sorry Maxwell...)

snip

Every cable in my home theatre is marked for one way usage, and I have
experienced the same results you describe. I also found that when I started
with stranded core cable, I had problems. Solid core made a difference. Go
figure.

BV.
www.iheartmypond.com

It has something to do with "pellicular effect" or "surface effect". Where DC
uses all available copper, AC uses only the surface of the wire. The higher the
frequency, the thinner the depth of the wire used by the current. At 20 000 Hz,
the top of the human spectrum, the maximum depth is about 1 mm so it is useless
to use strands of wire smaller than 1 mm.

I used a fabulous combination once: Two wires going from the amp. to the
speakers in parallel. A big one ( for arc soldering ) and a smaller one of very
high quality. The big one gave a very solid bass while the small one gave
cristaline highs.

P.S. Ask your wife before running such monster wires in your house...
Good night!

Benoît Morrissette
  #22  
Old February 12th 04, 10:21 PM
G=EMC^2 Glazier
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Hi oc As i understand it we use high voltage to reduce energy loss. For
safty we have the lines suspended from high pylons,and the wire covered
with a good insulator.(people don't like living under them or close by.
The voltage is steped up to several hundred thousand votes. for
electric trains,factoriers,etc. The voltage is stepped down to several
thousand volts. when the current reaches our homes the transformer steps
the voltage further down to 110 volts. I would think in North Canada
the very cold air would cause electricity to move with less lose of
energy. Bert

  #23  
Old February 13th 04, 12:08 AM
Bill Sheppard
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From Bert:

As i understand it we use high voltage to reduce energy loss.


Exactly. The higher the voltage the lower the loss per given resistance
(ohms value) in the lines. F'rinstance, say the lines present a total
resistance of 20 ohms. You can see that if you're transmitting at
500,000 volts, the lines present a much smaller loss than if you were
transmitting at say, 500 volts. And the advantage of high voltage
applies whether you're transmitting AC or DC.

Now that DC has shown an advantage over AC in extreme long distance
trasmission, Edison has become vindicated in a way, for his dogged
adherance to DC. oc

  #24  
Old February 13th 04, 11:29 AM
Benoit Morrissette
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On Thu, 12 Feb 2004 09:34:59 -0800 (PST), (Bill Sheppard)
wrote:

From BV:

As for the DC...I believe the usage of of
AC over DC is a cost thing. It would be
very costly and very lossy to push DC
around the country whereas you can
push AC very far and step it down where needed using a transformer.


Believe it or not, in some situations DC is more efficient for ultrahigh
voltage, long distance power transmission. This became feasible with the
advent of switching semiconductors used in the converter/ inverter
stations (which up-convert AC to ultrahigh voltage DC, and back down to
AC. A web search under 'high voltage DC transmission' will confirm this.
Also, in another post you discussed electron flow in a
conductor, but did not make a clear distinction between electron flow
and *flow of charge*. Flow of charge (electric flow) propagagates at the
speed of light minus the 'velocity factor', which can vary from about
76c to .80c depending on the conductor. But the valence electrons
themselves move very slowly by comparison. In an AC situation, they
remain essentially `in place' in the conductor. Electric flow in a
conductor (flow of charge) is not the same as *electron flow* in free
space, as in a vacuum tube.
Here's a discussion of some common misconceptions about
"electricity"-
www.amasci.com/miscon/eleca.html

oc

Very interesting reading, thanks!
Good night!

Benoît Morrissette
  #26  
Old February 13th 04, 01:48 PM
G=EMC^2 Glazier
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Hi oc and Benoit Thanks for that site oc that will get me thinking.
Benoit the eskimo getting electricity by looping the very high voltage
wires in the ground I found ineresting,but wonder if in reality they
might be getting the "heat"that the flow of electricity creates by the
resistance to its flow. ? Benoit you mention "induction" ,and going
with magnetic induction its field flows into the metal(say steel or
iron),and this turns the metal into a temporary magnet,and then the two
magnets attract each other. I use part of this in my own theory on
attraction over distance. I like reading these posts,and replying for it
brings back memories on how electricity works that I once knew and over
the years forgot. In Japan they make great use of induction motors,for
their use in maglev trains. Bert

 




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