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Re: portable dish idea - metallic thread



In a message dated 01-11-17 23:28:33 EST, you write:

> To get an reflecting surface I got the idea to take some thin copper wire 
>  (used in relais coils) and stich it in the original umbrella material :-) 
>  The thing I am not sure of if this will work because it will be equal as 
an 
>  dish with "chicken wire", only the wires are not electricaly connected.
>  

Hi William,

   I am testing this idea already.  I just have to finish up a feed to
see if this will work or not.

   I have taken a regular umbrella with a wooden handle and have 
already stitched the original umbrella material full of "metallic" 
thread from the local craft and hobby store.  The umbrella was
really cheap and wasn't even a vile buff colour. :-)

   I made horizontal and vertical stitches about one-half inch apart.  
In theory, this should create a mesh that appears solid at 
RF at 2.4 GHz and transform the umbrella into in a fully 
collapsable one meter dish.   (The threads/"wires" do not need to be 
electrically connected.)

   My concern is whether or not the "metallic yarn" is really 
reflective at 2.4 GHz or if it might actually absorb RF.  The
thread is shiny silver in color and a quick two second test in
the microwave confirms that it sparks like a metal. :-)  An ohm
meter test shows it conducts over short distances with low
resistance, but strangely it seems that it doesn't conduct 
over longer lengths.  I am not sure what the "metallic yarn" 
is actually made out of.  Does anyone know?  The spool is 
labelled "84% cotton and 16% metallic yarn".  Perhaps it is 
mylar?  Perhaps something else?  Does anyone know?

   I will let you (and the -bb) know after I finish testing if it is
successful.  

Douglas KA2UPW
dquagliana@aol.com
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