Abstract: A high frequency coaxial connector adaptor assembly for mating an APC-7 precision connector member to any of a set of coaxial connectors including N type, TNC type, and SMA type connectors. The invention utilizes a first connector body having an APC-7 interface at one end and having an open structure at the other end with an extended center conductor and outer conducting bushing to interface with any one of the set of coaxial connectors which are specially adapted at one end to engage the open structure of the first connector body. This structure permits an integral structure which does not significantly degrade or distort high frequency signals coupled to the coaxial connector while permitting interchangeable coaxial interfaces.