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Re: Aluminium Wire (fwd)



---------- Forwarded message ----------
Date: Sat, 29 Sep 2007 14:57:34 -0700
From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Aluminium Wire  (fwd)

Your exactly right Gary in all you said. It is definitely relative to 
the situation. But, realize as RF is increased in frequency, so is the 
usable geometry of the wire. There is a point where aluminum would be a 
poor choice as compared to copper, and there is a point where copper 
would be a poor choice as compared to silver. To say that a particular 
conductor is a poor choice for RF is not an educated statement (and I 
think that is your point). To say that a particular conductor in some 
particular stated application requiring x length at x frequency would be 
a poor choice may very well be valid. The details are everything and 
blanket statements are ridiculous in this particular situation.

To say that aluminum is fine because such and such application uses it 
(due to weight, cost, whatever) is another statement that is just as 
ridiculous. Coilers need to understand "when" it is bad and "when" it is 
not.

I remember the old "RF is bad with aluminum" posts from years ago on 
this List. I didn't understand then. Now that I understand the true 
implications, I realize it wasn't necessarily a "myth", but simply a 
poor choice of words that unfortunately ended up as a rule of thumb for 
coilers. This is one of those topics that should have been put to rest 
long ago.

Take care,
Bart


Tesla list wrote:

>---------- Forwarded message ----------
>Date: Sat, 29 Sep 2007 15:22:00 -0400
>From: "Lau, Gary" <Gary.Lau@xxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: RE: Aluminium Wire  (fwd)
>
>I don't dispute that copper is the best choice for a primary conductor.
>It is for several reasons, lower resistance by a factor of 1.6 for same
>conductor diameter being the best one.  Solderability and availability
>also better.  But I don't believe that the resistive behavior of
>aluminum changes at RF frequencies in a way that warrants advising folks
>to avoid it at all costs.  The testing that I did measuring the AC
>resistance showed NO frequency-dependant difference in resistance beyond
>the difference in DC resistance.  Calling aluminum wire a loser just
>because it exhibits a 1.6X higher resistance over same-sized copper wire
>is like saying 14 gauge wire is a loser because it also has 1.6X (yes,
>what a coincidence!) the resistance that 12 gauge wire has.  So a 12
>gauge aluminum primary will behave identically to a 14 gauge copper
>primary, regardless of frequency.  It's all relative.
>
>My point is that blanket statements that aluminum is bad at RF
>frequencies leads folks to silly behaviors, like saying that RSG
>electrode holders should not be made of aluminum because RF currents are
>involved.  
>
>Gary Lau
>MA, USA
>
>  
>
>>From: resonance <resonance@xxxxxxxxxxxx>
>>To: Tesla list <tesla@xxxxxxxxxx>
>>Subject: Re: Aluminium Wire  (fwd)
>>
>>
>>
>>You are not trying to send peak currents of 500 to 5000 Amps thru this
>>conductor.  In the pri circuit copper is still the best choice.  A
>>    
>>
>typical
>  
>
>>medium size coil with a 0.05 uF Maxwell cap will hit 3,000 Amps peak
>>    
>>
>at 200
>  
>
>>Khz.
>>
>>Dr. Resonance
>>
>>Resonance Research Corp.
>>www.resonanceresearch.com
>>
>>
>>----- Original Message -----
>>From: "Tesla list" <tesla@xxxxxxxxxx>
>>To: <tesla@xxxxxxxxxx>
>>Sent: Thursday, September 27, 2007 11:05 PM
>>Subject: Re: Aluminium Wire (fwd)
>>
>>
>>    
>>
>>>---------- Forwarded message ----------
>>>Date: Mon, 17 Sep 2007 21:12:59 -0700
>>>From: Dr.Hankenstein <Dr.Hankenstein@xxxxxxxxxxxxx>
>>>To: Tesla list <tesla@xxxxxxxxxx>
>>>Subject: Re: Aluminium Wire  (fwd)
>>>
>>>Why would aluminum be considered "bad" for RF?
>>>My antennas work great...and they're made out of aluminum!
>>>So does the top-load on my tesla coil...five foot cross section,
>>>      
>>>
>5kva
>  
>
>>>input, 10 foot sparks....and it's aluminum! see:
>>>http://www.drspark.org/images/wwt6.jpg
>>>Perhaps working with unconventional materials and designs is what
>>>      
>>>
>coiling
>  
>
>>>is all about; what do you think?.
>>>
>>>Woo
>>>
>>>
>>>      
>>>
>>>>[Original Message]
>>>>From: Tesla list <tesla@xxxxxxxxxx>
>>>>To: <tesla@xxxxxxxxxx>
>>>>Date: 9/27/2007 7:52:22 PM
>>>>Subject: Re: Aluminium Wire  (fwd)
>>>>
>>>>
>>>>---------- Forwarded message ----------
>>>>Date: Thu, 27 Sep 2007 18:21:09 -0500
>>>>From: resonance <resonance@xxxxxxxxxxxx>
>>>>To: Tesla list <tesla@xxxxxxxxxx>
>>>>Subject: Re: Aluminium Wire  (fwd)
>>>>
>>>>
>>>>
>>>>Alum will work but limits your peak primary current.  Alum is not
>>>>        
>>>>
>very
>  
>
>>>>good
>>>>at RF frequencies.  It is used for 60 Hz commercial power
>>>>        
>>>>
>transmission
>  
>
>>>>lines
>>>>but not good above a few hundred Hz.
>>>>
>>>>Been there, done that, and took measurements.  Alum was a loser for
>>>>        
>>>>
>best
>  
>
>>>>coil performance.
>>>>
>>>>Dr. Resonance
>>>>
>>>>
>>>>
>>>>Resonance Research Corp.
>>>>www.resonanceresearch.com
>>>>
>>>>
>>>>----- Original Message -----
>>>>From: "Tesla list" <tesla@xxxxxxxxxx>
>>>>To: <tesla@xxxxxxxxxx>
>>>>Sent: Thursday, September 27, 2007 5:39 PM
>>>>Subject: RE: Aluminium Wire (fwd)
>>>>
>>>>
>>>>        
>>>>
>>>>>---------- Forwarded message ----------
>>>>>Date: Thu, 27 Sep 2007 11:16:32 -0400
>>>>>From: "Lau, Gary" <Gary.Lau@xxxxxx>
>>>>>To: Tesla list <tesla@xxxxxxxxxx>
>>>>>Subject: RE: Aluminium Wire  (fwd)
>>>>>
>>>>>Radio Shack used to sell some heavy ~.125" Aluminum "ground"
>>>>>          
>>>>>
>wire, for
>  
>
>>>>>grounding TV antennas.  Not sure if they still sell this.  But
>>>>>          
>>>>>
>why use
>  
>
>>>>>Aluminum wire at all?  Copper is more common, solderable, and a
>>>>>          
>>>>>
>better
>  
>
>>>>>conductor.  Al will work though.
>>>>>
>>>>>Gary Lau
>>>>>MA, USA
>>>>>
>>>>>          
>>>>>
>>>>>>-----Original Message-----
>>>>>>From: Tesla list [mailto:tesla@xxxxxxxxxx]
>>>>>>Sent: Thursday, September 27, 2007 9:47 AM
>>>>>>To: tesla@xxxxxxxxxx
>>>>>>Subject: Aluminium Wire (fwd)
>>>>>>
>>>>>>
>>>>>>---------- Forwarded message ----------
>>>>>>Date: Thu, 27 Sep 2007 10:48:54 +0100
>>>>>>From: Chris Swinson <list@xxxxxxxxxxxxxxxxxxxxxxxxx>
>>>>>>To: Tesla list <tesla@xxxxxxxxxx>
>>>>>>Subject: Aluminium Wire
>>>>>>
>>>>>>Hi all,
>>>>>>
>>>>>>Does anyone know if you can buy Aluminium Wire ? Pondering doing
>>>>>>            
>>>>>>
>some
>  
>
>>>>>>testing over copper vs Aluminium Wire with a very small coil,
>>>>>>            
>>>>>>
>though
>  
>
>>>>>looks a
>>>>>          
>>>>>
>>>>>>pretty are kind of thing :-(
>>>>>>
>>>>>>Chris
>>>>>>
>>>>>>
>>>>>>            
>>>>>>
>>>>>
>>>>>
>>>>>          
>>>>>
>>>>
>>>>        
>>>>
>>>
>>>      
>>>
>>
>>    
>>
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