Re: Aluminium aka Aluminum Wire (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Mon, 1 Oct 2007 22:53:01 -0700
From: Ray von Postel <vonpostel@xxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Aluminium aka Aluminum Wire (fwd)

I would think that if the metal used in the wire to wind a coil made 
any difference to the INDUCTANCE, that it would be a factor in 
equations used to calculate INDUCTANCE.  I don't find it in equations 
used by NBS/NIST when computing the inductance of standard inductors.  
Does any one say they have missed something?

Two coils having IDENTICAL geometry, one wound with aluminum and the 
other copper will have the same INDUCTANCE. However, the losses in the 
coil wound with aluminum will be higher because it will have a higher 
resistance.

Similarly, capacitance is not dependent upon the material of the 
conductor and only upon the geometry.  This assumes the dialectic 
remains the same in every way.

Resistance,  inductance, and  capacitance are not frequency dependent.  
It is only when you connect them together in some sort of circuit that 
frequency effects are noted.  No one has ever built an electrical 
component where all three were not present.  All you can do is try and 
minimize or maximize them depending on what you are trying to 
accomplish.  A good example of what I am talking about is a resistor 
wound from resistance wire on a ceramic tube.  It not only has 
resistance but inductance and distributed capacitance.  As such it can 
be regarded as a high loss solenoid and will exhibit the same 
characteristics as the secondary of a Tesla coil but in different 
amounts.  It will be self resonant at some frequency.

As far as aluminum wire is concerned it has its place, but I seem to 
remember that after WW II a lot of houses were wired with aluminum.  
Many fires resulted because of poor connections to convenience boxes 
etc. So, if you are going to use it in coiling it might be well to find 
out what it takes to make good connections using it.

Cooper-weld wire was developed as an engineering compromise.  Antennas 
for low frequencies, such as the Beverage, flat top and multi-curtain 
rhombic become physically large.  The use of copper-weld is a 
compromise between and among cost, strength, and r. f. resistance.

Ray


On Oct 1, 2007, at 7:52 PM, Tesla list wrote:

>
> ---------- Forwarded message ----------
> Date: Mon, 01 Oct 2007 16:01:41 -0700
> From: Ed Phillips <evp@xxxxxxxxxxx>
> To: Tesla list <tesla@xxxxxxxxxx>
> Subject: Re: Aluminium aka Aluminum Wire (fwd)