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<DIV>The tangents that some threads create are often much more interesting than
the original intent of the thread. </DIV>
<DIV> </DIV>
<DIV>Keith I would say it's not a good idea. If you built a fuse out of this
material, (done everyday BTW), I suggest you build it large enough to
accomodate the person flying it (vbg). I know Bill, Don Ramsey and Al Glenn and
probably several more, flew or still fly "Faraday Cages" for a living</DIV>
<DIV> </DIV>
<DIV>Now, how we went from measuring surface flatness to "shielding" devices
from EMI/RFI (regardless of what the emitting source is), is beyond me</DIV>
<DIV> </DIV>
<DIV>MattK</DIV>
<DIV> </DIV>
<DIV>In a message dated 11/23/2004 4:32:15 PM Eastern Standard Time,
tkeithb@comcast.net writes:</DIV>
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<DIV><FONT face=Arial size=2>In other words, if you built your fuse out of
this material you'd probably want to run your antenna externally.
;-)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE dir=ltr
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<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mailto:bob@toprudder.com href="mailto:bob@toprudder.com">Bob
Richards</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=mailto:discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, November 23, 2004 2:59
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Measuring Surface Flatness
(was "Cabinet Grade Particle Board")</DIV>
<DIV><BR></DIV>
<DIV>John,</DIV>
<DIV> </DIV>
<DIV>I disagree. The definition of a "Faraday <STRONG>CAGE</STRONG>",
which is what Bill said, is a completely conductive sealed enclosure.</DIV>
<DIV> </DIV>
<DIV>Also, the edges don't have to be fully bonded together for RF
protection. They can be stitched together at intervals depending on how high
in frequency you want attenuation. The closer the spacing, the higher the
cutoff frequency. Obviously, if you want cutoff up into the gigahertz range,
you pretty much need a continuous bond.</DIV>
<DIV> </DIV>
<DIV><A
title=http://www.boltlightningprotection.com/Elemental_Faraday_Cage.htm
href="http://www.boltlightningprotection.com/Elemental_Faraday_Cage.htm">http://www.boltlightningprotection.com/Elemental_Faraday_Cage.htm</A></DIV>
<DIV> </DIV>
<DIV><A title=http://en.wikipedia.org/wiki/Faraday_cage
href="http://en.wikipedia.org/wiki/Faraday_cage">http://en.wikipedia.org/wiki/Faraday_cage</A></DIV>
<DIV> </DIV>
<DIV>Bob.</DIV>
<DIV><BR><BR><B><I>John Ferrell <johnferrell@earthlink.net></I></B>
wrote:</DIV>
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<DIV><FONT face=Arial size=2>Sorry to get picky, but a Faraday shield is
not an electromagnetic field, it is an electrostatic shield. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>An rf tight room needs the edges fully bonded
together and a Faraday shield requires that they be insulated.
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I think everyone knows what is being said,
but I felt obliged to add the detail. </FONT></DIV>
<DIV> </DIV>
<DIV>John Ferrell <BR>My Competition is not my enemy! <BR><A
title=http://dixienc.us/
href="http://dixienc.us/">http://DixieNC.US</A><BR></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mailto:bob@toprudder.com href="mailto:bob@toprudder.com">Bob
Richards</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=mailto:discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, November 22, 2004
1:06 PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Measuring Surface
Flatness (was "Cabinet Grade Particle Board")</DIV>
<DIV><BR></DIV>
<DIV>That's what it is. No RF gets in or out. Something like 110dB
attenuation.</DIV>
<DIV> </DIV>
<DIV>Bob.</DIV></BLOCKQUOTE></BLOCKQUOTE></BLOCKQUOTE></FONT></BLOCKQUOTE></DIV>
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