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December 22nd 03, 04:16 PM

On 22 Dec 2003 07:07:20 -0800, (Art Unwin KB9MZ)
wrote:

Richard,
Thank you for that extensive reply. I now see that a
floating coax shield would be ineffective as a screen

A floating coax is as good as any shield to be used for a Faraday
Shield. It is used extensively in balanced loop constructions
everyday.

since it would not discriminate

You still don't get the purpose of the shield. It discriminates very
effectively - its whole purpose in life. Research Richard's comments
in Google.

I initially looked at a picket fence as having
two hortizontal members as well but now I see it as more
of a fork design with the tines at a 90 degree
axis to the axis of the secondary inductance and parallel
to the actual coils.

No such requirement exists - there are NO alignment issues. The
reason they fork is to eliminate current flow. Every power
transformer on this planet employing a Faraday Shield does it with a
solid sheet of copper. The copper does not conduct nor support
current loops because it is connected to ground at one point only.
Hence, such a design is consistent with the "fork" metaphor, if you
only think of it as having one, extremely wide tine.

Art, you have Terman, why don't you consult him?

We will see if works out for both
lightning and static as my tower is grounded together
with a heavy separate aluminum cable connected to my
ground grid. It has yet to be hit by lightning however

Best regards

Hi Art,

You should consult the Code as to grounding methods.

73's
Richard Clark, KB7QHC