  We show both theoretically and experimentally that a pair of inductively
coupled active LRC circuits (dimer), one with amplification and another with an
equivalent amount of attenuation, display all the features which characterize a
wide class of non-Hermitian systems which commute with the joint parity-time PT
operator: typical normal modes, temporal evolution, and scattering processes.
Utilizing a Liouvilian formulation, we can define an underlying PT-symmetric
Hamiltonian, which provides important insight for understanding the behavior of
the system. When the PT-dimer is coupled to transmission lines, the resulting
scattering signal reveals novel features which reflect the PT-symmetry of the
scattering target. Specifically we show that the device can show two different
behaviors simultaneously, an amplifier or an absorber, depending on the
direction and phase relation of the interrogating waves. Having an exact
theory, and due to its relative experimental simplicity, PT-symmetric
electronics offers new insights into the properties of PT-symmetric systems
which are at the forefront of the research in mathematical physics and related
fields.
