[600MRG] Stainless Antenna Wire Continued

[William E. Isakson]

Stainless is probably not in the programs, Frank, because the program does
not cover a hysteresis effect.  The hysteresis losses would change with
frequency, lower frequencies being worse.
Just for the record, the scientific work I did long ago was in the magnetic
properties of iron containing materials.   Hysteresis was not my main
theme, though iron, chrome, and nickel were all major in our projects, but
it is a big issue and its effects certainly appeared.   Our frequencies for
modulation of fields were much lower than you are using but even at 630
meters or 160 meters, stainless would show hysteresis energy absorption.  I
suppose if you were at the south pole you might use it for a heating effect
to clear the ice from the antenna,something that would require some
experimentation to find out.
I really would not use stainless (or iron) antennae for serious radio,
Frank, although I note that many of those 2 meter and 440 whips that were
so common on autos were indeed stainless.
Bill

--------


Bill Isakson     AC6QV
Roseburg, Oregon USA
bill.isakson at gmail.com



On Sat, May 6, 2017 at 4:04 AM, Frank Lotito <k3dz at live.com> wrote:

> In a recent posting I asked about using stainless steel antenna mast guy
> wires as part of the radiating system.  Thank you for the replies including
> the direct e-mails to me. I decided to use EZNEC 6.0 to model a few
> comparative examples.  These models might give me a little more insight
> whether or not a more exotic guy wire material / construction would be
> necessary.
>
> To start, I will model simple antennas using two different materials, such
> as the antenna using only 18-8 stainless, or only copper.
>
>  EZNEC 6.0 gives the user the opportunity to select a few different
> antenna materials, but not stainless.  EZNEC 5.0 has a little longer list
> of wire materials, but not stainless.   However, the user can input his
> choice of wire material by inputting two units of measure for that material:
>
>  1 - Resistivity in ohm-meter
>  2 - Relative permeability, reference copper = 1. (All the EZNEC materials
> 5 & 6 choices have a permeability of 1, but none of the materials are
> alloys of iron.)
>
>  Can someone suggest an online source for the two above units of measure
> for materials such as stainless 18-8, 316, 302 ?  And, for the $64
> question, does the magnitude of these these units  vary with frequency?  I
> would think the permeability of iron bearing alloys does. The frequencies
> of interest (in round numbers) are 0.500 MHz, 50 MHz and 150 MHz.
>
>  Thank you and 73  Frank K3DZ / WH2XHA
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