configuration 50 where each direction of transmission is served by a two stage amplifier configuration such as 51 formed by two different integrated amplifier assemblies cards 52 and 54 this bi directional configuration 50 is the most preferred one a so called east west configuration which cannot be implemented using neither the conventional two stage integrated assembly fig1 b nor its modified version a so called mid stage 55 of both of the unidirectional configurations utilizes the real gap between inputs and outputs of the two cards 52 and 54 and may serve for inserting optical elements between the stages of the unidirectional configurations the control communication channels schematically shown and marked 56 and 58 are also arranged between the cards all or some external connections can be arranged for example using a back plane 57 of a shelf structure holding the cards 52 54 fixed couplings may be formed in the back plane for the purpose fig3 d illustrates how the configuration 50 can be realized using the proposed universal integrated assembly of fig2 two assemblies 20 and 120 are shown and their connections demonstrate how the mid stages are formed and how new control communication channels between the newly formed two stage configurations are formed using portions of the control communication circuits of the two separate assemblies 20 120 one of the two newly formed unidirectional configurations is shown by a dotted contour 60 its newly formed control communication channel is marked 62 the similar configuration with its control communication channel is.