Please excuse the error in the third paragraph of the earlier post.
Higher permeability increases resistance, not frequency, because it
reduces the depth of current due to skin effect.
Red wrote:
>Any of the stainless steel alloys are suitable for grounding an antenna
>element to the boom to prevent arcing. Moderately high impedance won't
>prevent them from limiting the voltage difference between the element
>and the boom to less than the voltage needed to initiate an arc or even
>a corona discharge. Half the energy of a lightning strike is below
>one MHz and half is at higher frequency.
>
>However, the resistance of some stainless steel alloys, especially at
>the higher RF frequencies, may cause some loss when the objective is to
>carry part of the antenna current. While skin effect won't prevent a SS
>strap from effectively grounding the element to the boom as far as
>lightning is concerned, it will cause some loss of 160 meter and 80
>meter signals (or higher).
>
>Skin effect depends upon frequency and the permeability of the metal.
>Higher frequency limits the depth of current and increases resistance.
>Higher permeability also limits the depth of current and increases
>_frequency_ (should be resistance)
>
>Some stainless steel alloys are non-magnetic and thus their skin effect
>is less pronounced than that of the magnetic alloys.
>
>The skin effect is much more serious in conductors intended to limit
>lightning potential for the purposes of protecting equipment in the ham
>station, where an ideal is to approach zero impedance. While any
>stainless steel strap may prevent arcing, some are definitely undesired
>in applications where their purpose is to protect equipment.
>
>73 de WOØW
>
>
>
>
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