At RRCAT, for proton accelerator and infrastructure facility, high power (30kW) solid state amplifier, operating at 352 and 505.8 MHz has been designed. In this design, kW level RF power will be obtained by summing power output of multiple devices, developed in the form of amplifier modules. Power summing action is achieved by power combiner operating in kW power regime. In view of this, theoretical study and prototype testing of various combiner structures, suitable for 300 to 800 MHz frequency range, was carried out. Starting with development of eight way radial combiner at 352 MHz, 505.8 MHz and 704 MHz, improved eight way and sixteen way structures were designed, for using up to 5kW and 8kW power level. Satisfactory testing encouraged fabricating and testing more numbers of similar combiners. For directional power measurement, in kW level amplifier, wideband (300-800 MHz) low power (up to 1kW) and high power (4kW) directional couplers were designed and developed.

5kW, 8- port Combiner at 352, 505.8 and 700 MHz	5kW, 16 ports combiner at 352 MHz	5kW, 16 ports Power combiner at 505.8 MHz	Measured performance of RF Power Combiners

8kW combiner with 2 ports at 352 MHz	High power Directional coupler and measured perforamance (right)

Both of these couplers, based on rectangular coaxial line, were fabricated and tested in multiple to assure repeatable results.