blocking radio waves
The real problem in making a shielded area like you propose isn't so
much the material as the seams and wires. Connection between panels has
to be virtually continuous, or you'll have very ineffective shielding no
matter what material you use. You need a completely sealed box, floor
and ceiling included, with no unbonded hole or seam larger than a very
small fraction of a wavelength in size. Aluminum is hard to bond well,
so that's a poor choice. Doorways are particularly problematic - make a
visit to a local EMC lab to see what measures are typically taken. The
sealing requirements become more stringent as frequency increases.
An equally or even more difficult problem is getting power, telephone,
and any other conductors through the shield without allowing unwanted
signals to come in with them.
Roy Lewallen, W7EL
merlin-7 wrote:
When I build my new shack, I was thinking about lining the inside of the
plywood with something, before it is installed, that would block outside
radio transmissions inside the shack.
Mostly in the 2 meter range and higher.
Would simple aluminum foil work?
If so what frequency range could I expect it to work in?
If not any suggestions on material? The cheaper the better.
I know there is a term for a room like this but I can not rember it..faraday
chamber?
The shack will be 12 foot by 16 foot, right next to my 60' tower, with HF
and 2m antennas on it. I have no idea how they will interact with such a
building...
Thanks
Joe
|