  The paper discusses technical aspects of constructing a highly versatile
multi-photon source. The source is able to generate up to four photons which is
sufficient for a large number of quantum communications protocols. It can be
set to generate separable, partially-entangled or maximally-entangled photon
pairs with tunable amount of purity. Furthermore, the two generated pairs can
be prepared in different quantum states. In this paper, we provide all the
necessary information needed for construction and alignment of the source. To
prove the working principle, we also provide results of thorough testing.
