Mike Coslo wrote:
If RF energy has mass ...

The mass of each photon is:

m = e/c2 = h/c*lambda

where h is Planck's constant, c is the speed of light,
and lambda is the wavelength.

The reason that your experiment won't work is that
equal amounts of energy are being supplied to and
radiated (or conducted) from a transmitting antenna.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com