On Oct 9, 6:37 pm, wrote:
On Oct 9, 8:28 pm, wrote:

On Oct 9, 12:18 pm, RHF wrote:

On Oct 9, 10:00 am, billy wrote:

What material can be used for shield against potentially dangerous
levels of radio waves. Lets say outside my bedroom is a radio
communication device. What material could stop the waves from
entering. Cement? Lead? How thick?

Aluminium Siding -and- Aluminium Screened Windows

I have a MSEE, but E&M is not my specialty. However, since aluminum is
not a ferous material, I believe the H wave will penetrate it. RF
shielding paint is generally nickle for that reason. I don't recall if
"mu metal" is ferous or not.

Turn your degree in!

Faraday cages, AKA screen rooms, are used to isolated a space from the
outside
world. They use copper mesh, with the junctions welded, and achieve
isolations of
from 80dB up to ~120dB, more dB isolation requiring multiple "walls".
Think nested
Russian dolls.

A RF/EM "wave" consists of both E and H fields. Any conductive case
with completely
conductive seams and walls will stop any RF/EM field.

[snip]

Not any. Skin depth comes into play so that any Faraday cage is going
to have a lower cut-off frequency below which attenuation falls off.
The size of holes set an upper cut-off frequency above which
attenuation falls off. A Faraday cage, therefore, looks like a band-
stop filter for RF/EM fields - the thicker the walls and the smaller
the holes, the wider the bandwidth..

Tom