A monolithic distributed mixer 10 includes a plurality of dual gate field effect transistors (FETs) 32, 38, 44 and 50 and first 18 and second 18', 26 and 20', 22', 24 and 26', corresponding pluralities of T shaped constant K-filters 20, 22, 24 connected respectively to first and second gates of the dual gate FETs 32, 38, 44 and 50 for displaying in time the LO and RF voltages applied thereto whereby the phase shift is the same at each filter and the phase difference between the LO and RF at each FET 32, 38, 44 and 50 is equal. Thus, the IF energy developed at each drain is in phase. The plurality of dual gate FETs 32,38,44 and 50 have their drains commonly connected for summing the IF outputs thereof to provide a flat response throughout the bandwidth which is limited only by the cutoff voltages of the FETs or first and second pluralities of K-filters which act as low pass filters.