Abstract: This paper describes the design and development of a Ka‐band Modulator Assembly which is currently in EM/EQM production phase at Bosch SatCom. The assembly is part of a complete transmit section for the European multimedia satellite system EuroSkyWay (ESW) planned by Alenia Spazio and developed in the frame of the ARTES 3 line, which is a co‐funded programme between ESA and the industry. The modulator assembly receives the digital data streams, performs the appropriate formatting and baseband processing according to the DVB‐S standard and directly modulates the Ka‐band carriers. The modulator assembly incorporates all functions to be autonomously operated on a spacecraft platform. Each function has been realized fully redundant and consists of DC supply, carrier frequency generation, carrier distribution and switching, direct modulation, a static baseband switching, the TM/TC interface and the signal distribution. Up to 10 active Ka‐band channels operating with three different carriers can be supported. To deal with the complex signal distribution the assembly is constructed using a common baseplate containing the central infrastructure as well as all external DC, TM/TC and Data interfaces. With this approach signal integrity as well as spurious emission/susceptibility are tightly controlled. The RF functions and the DC/DC converters are realized as plug‐in modules which gives flexibility w.r.t. the number of communication channels and carriers. Furthermore testability and integration procedures are improved by this plug‐in module concept. Mechanical stiffness and the heat transfer has been optimized to comply with the S/C thermal and mechanical interfaces. The assembly is capable to cover typical multi‐media applications and the results prove that highly integrated multi‐functional assemblies are ready to use.