A portable system for non-destructively characterizing spot welds that includes at least one matrix phased array probe and a body, wherein the body is designed to be hand-held and further includes an ergonomically designed outer casing; at least one input for connecting to the at least one matrix phased array probe; ultrasonic phased array transmitting and receiving circuitry in electrical communication with the at least one input; a touch screen computer that further includes at least one data processor running software that includes at least one imaging algorithm for processing data received from the probe and generating color coded ultrasonic C-scan images of characterized welds; and at least one monitor for displaying the color coded ultrasonic C-scan images of the characterized welds in real time.