Abstract: In order to form a modular interface between a DUT board, which is housing devices under tests (DUT), to cables connected to a test head, a board spacer is provided that has an array of connectors. Each cable is connected to a respective connector, and the DUT board contains a corresponding array of connection points which are less than or equal to the number of connectors in the arrays on the board spacer. In this way, a common board spacer can be used to connect the cables to DUT boards housing different types of DUTs since the location of the connection points on the board spacer is known and kept constant. This interface allows a high speed and high fidelity connection between the test head and the devices on the DUTs for frequencies in excess of 50 MHz.