  We consider a parity-time ($\mathcal{PT}$-) symmetric waveguide consisting of
a localized gain and loss elements separated by a variable distance. The
situation is modelled by a Schr\"odiner operator with localized complex
$\mathcal{PT}$-symmetric potential. Properties of the latter Hamiltonian are
considered subject to the change of the gain-to-loss distance. Resonances,
spectral singularities and eigenvalues are analyzed in detail and discussed in
the context of the associated laser-absorber modes and $\mathcal{PT}$-symmetry
breaking phase transition. Increasing gain-to-loss distance creates new
resonances and spectral singularities which do not exist in the waveguide with
adjacent gain and loss. In the limit of large gain-to-loss distance, the
waveguide features a ladder of resonances which can be transformed to a ladder
of complex eigenvalues by means of the change of the gain-and-loss amplitude.
