It may be worth noting that some sheet rock (plaster board), ceiling
panels, and insulation (foam board) have metallic backing which increase
the difficulty of electromagnetic ingress or egress. Screen room? no,
attenuation of signals or interference ? to some degree, yes, maybe,
based on twenty years working in RF communications in large commercial
buildings with these materials and metallic oxide glass and metal floor
pans for concrete.
73 ES DX,
Gary - AB9M
On 12/5/2016 12:19 PM, jimlux wrote:
> On 12/5/16 8:55 AM, Grant Saviers wrote:
>> We built a Faraday cage big enough for an engineer and equipment and
>> learned that a special screen material is needed. Regular copper
>> screening has lots of crossovers that aren't really connected or worse
>> are oxidized contacts and can make the noise worse. A tech was assigned
>> to solder the wires in strips every 4 inches x,y,z, which took a couple
>> of days and made for a very unhappy tech. The results were ugly but
>> RF ok.
>
> You want "welded screen" as opposed to "woven screen" - standard steel
> hardware cloth would probably work.
>
> "real" screen rooms are made with aluminum or galvanized steel sheet
> (which is probably cheaper than screen, and a whole lot easier to make
> sure it connects to everything).
>
>
>
>
>
>>
>> I don't see a benefit for a station. IMO, it's a better use of time to
>> concentrate on a good building perimeter ground, the entry plate, good
>> chokes, and insuring no RFI sources from equipment inside the building.
>
>
> Indeed...
>
> And you will find it very inconvenient that cellphones and VHF/UHF HTs
> don't work (or work poorly) in your shack, too. The old shack at JPL
> was a building with metal lined walls, and if the door closed, you
> can't raise the JPL repeater with a HT.
>
>
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