# Could a bluetooth beacon communicate with another bluetooth device within a faraday cage?

If I placed two devices inside of a faraday cage, one of which was a bluetooth beacon which emitted a bluetooth signal, the other was a cell phone which received bluetooth signals, would they be able to communicate?

Similarly, could two devices communicate on another radio frequency protocol?

I understand that the faraday cage would block signals from leaving the cage, or signals from coming in; what is unclear is whether there is still an electromagnetic field within the cage.

Thanks friends.

• I have in mind 10x, but I think what happens in the small-cage case also depends on the behavior of the surface of the cage. You might test it. Bluetooth is $\lambda = c/\rm 2.4\,GHz = 0.15\,m$, about the size of most devices. Put two together in a paper bag and wrap the bag neatly and completely in a few layers of aluminum foil. If the devices can still talk to each other, they'll work in a larger enclosure as well. – rob Feb 1 '17 at 2:07