Re: Electrical Properties of Aluminum and Network Analyzer was : RE: Brass

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com>

Maybe so, but if there is one thing I've learned being in the business of
working with high voltage and high power (RF) systems is that circuit
elements ALWAYS behave much differently at
high voltage / high power than what simulations, or low power measurements /
analysises provide.  Its the nature of the beast.  There are a lot of
secondary effects which cannot be picked up
by a low power active measuring devices that only show their ugly heads at
high voltage / high power.  I do agree you can get some basic, comparative
measurements as you stated, but if you
truly want a true represenation of how the materials behave at the levels
tesla coils will subject to them, you'll need to ditch the network /
impedance analyzer and go with some true hard measurements
from a system running the materials in question at the power levels you are
interested in.

 > I disagree.  The fundamental circuit elements in a real primary inductor,
 > Rdc, Rac, L, and C, are all linear.  At any given frequency, these
 > parameters are constant regardless of voltage or current levels.  If there
 > is some _significant_ loss mechanism that is non-linear, I'm not aware of
 > it and I would be interested to learn more if you know of one.  Corona
 > losses are not linear, but for similar coil geometries, an Al coil would
 > have the same corona losses as a Cu coil.  A curve plotting AC resistance
 > vs. frequency on a network analyzer for similarly constructed copper and
 > aluminum inductors would be a definitive comparison.  If AC resistance of
 > the Al coil is higher on the network analyzer, it most certainly will have
 > comparably higher losses in a TC tank.  How much an x% increase in primary
 > AC resistance may impact the secondary spark length is still an open
 > question however.
 >
 > Terry wrote:
 >  >Radio Shack sells like 10 gage aluminum ground wire for TV antennas.
Bare
 >  >copper wire of the same gage is common.  Just making a coil of each and
run
 >  >them in a high RMS current primary circuit (secondary system not needed)
 >  >would do it.  I have too many things going on at the moment, but maybe
 >  >someone else ;-))
 >
 > It was my plan to construct an aluminum coil for my series of network
 > analyzer AC resistance measurements, but I came up empty searching at Home
 > Depot and flea markets for Al wire.  Radio Shack - I never would have
 > guessed!  Their web site describes a 40 ft roll of 8 gauge aluminum ground
 > wire.  That sounds a bit stiff, but I'll check it out and see.  If they
 > stock it and if it is solid, I will construct and network-analyze an
 > aluminum primary, both before and after a salt-water soak.
 >
 > Regards, Gary Lau
 > MA, USA
 >
 >
 >
 >
 >