This is a PXI signal insertion and monitor matrix with switched pass thru connections on both X and Y axis. It is also available in a 34x4 format and can be used for signal insertion and monitoring purposes on connections between the UUT and test system. Each pass thru connection from LX to X can be open or closed to allow the programmatic disconnection of the signal to check the response of the UUT. The matrix can be used to connect test equipment, such as a DMM or scope, to monitor the pass thru signals via Y connections while the LY connections can be used to insert a fault condition or insert external signals. When external signals are injected the LX connections can be opened and the LY connections closed. The matrix size can be expanded by linking Y connections across multiple modules. Larger matrices can be created with switched isolation relays if connected by the LY connections.