  This is the second step of a program to use anharmonic plane waves as basis
set in non-perturbative quantum field theory. The general framework developed
previously is applied to quantum electrodynamics. To test the compatibility
with standard quantum electrodynamics, the Feynman rules are generalized to
anharmonic waves by expanding the field operators into anharmonic plane waves.
A sum rule for the Fourier coefficients of anharmonic waves ensures that the
generalized Feynman rules are equivalent to the standard rules after summing
over all harmonics. It is possible to construct diagrams for the generation of
harmonics. They are of O(alpha^2) for photons and of O(alpha) for electrons. To
tackle intrinsically non-perturbative phenomena it is proposed to insert
anharmonic field operators into the Dyson-Schwinger equations while retaining
only the lowest harmonics.
