I am trying to run a 6400M with a new Elecraft KPA-1500 amp without using DDutils and any computer. I also do not want to use the RF sensing in the amp. I am told the amp will track the Flex using one of the two USB ports. I have a RT System USB cable with a chipset that the Flex recognizes in setup. The cable is USB to 1/8 inch TRS and should communicate with the amp. Any help would be appreciated if you are doing this now.