A system (100, 920) comprising: a control system and a modular device communicatively coupled through a cable assembly and a connector assembly (380, 600, 700, 850, 900, 922), the modular device configured to be inserted into a body and configured to at least one of detect external signals or emit energy, the connector assembly having a plug connector (124, 200, 400, 602, 702, 800, 852, 902, 924) and a receptacle connector (126, 300, 500, 604, 704, 854, 904, 926), wherein a centerline (210, 410, 610, 710, 810, 950) extends through the cable assembly; the plug connector comprising an elongated plug substrate (220, 430, 614, 616, 706, 940) and a mating array (226, 288, 416, 620, 708, 942) of electrical contacts (228, 622, 712, 944) supported by the plug substrate, the plug substrate projecting in an axial direction along the centerline; and the receptacle connector comprising a receptacle housing (306, 506, 624, 720, 930) and a system array (340, 342, 595, 597, 722, 962) of electrical contacts (344, 596, 724, 964) secured to a printed circuit (550, 552, 992), the receptacle housing having an enclosed slot (320, 520, 630, 632, 725, 960) that is sized and shaped to receive the plug substrate during a mating operation in which the plug substrate is inserted into the enclosed slot in the axial direction, wherein the system array and the mating array engage each other along a mating zone (390, 391, 593, 966) within the enclosed slot, the mating zone extending essentially parallel to the centerline, and the receptacle connector having a mating mechanism (560, 993) including an actuator (564, 568, 995) and a cam plate (562, 566, 994) that are operably engaged with each other, the cam plate being positioned side-by-side and forming a slidable interface with the actuator, the cam plate including ramps (570, 996) and the actuator including recesses (572, 997) that receive the ramps, wherein the electrical contacts of the system array of the printed circuit are movable, as a group, in a radial direction that is perpendicular to the centerlinc when the plug connector engages the actuator, the actuator being pushed in a mating direction of the plug connector and being operably engaged to the cam plate such that the cam plate is driven in the radial direction causing the printed circuit to move towards the enclosed slot. a control system and a modular device communicatively coupled through a cable assembly and a connector assembly (380, 600, 700, 850, 900, 922), the modular device configured to be inserted into a body and configured to at least one of detect external signals or emit energy, the connector assembly having a plug connector (124, 200, 400, 602, 702, 800, 852, 902, 924) and a receptacle connector (126, 300, 500, 604, 704, 854, 904, 926), wherein a centerline (210, 410, 610, 710, 810, 950) extends through the cable assembly; the plug connector comprising an elongated plug substrate (220, 430, 614, 616, 706, 940) and a mating array (226, 288, 416, 620, 708, 942) of electrical contacts (228, 622, 712, 944) supported by the plug substrate, the plug substrate projecting in an axial direction along the centerline; and the receptacle connector comprising a receptacle housing (306, 506, 624, 720, 930) and a system array (340, 342, 595, 597, 722, 962) of electrical contacts (344, 596, 724, 964) secured to a printed circuit (550, 552, 992), the receptacle housing having an enclosed slot (320, 520, 630, 632, 725, 960) that is sized and shaped to receive the plug substrate during a mating operation in which the plug substrate is inserted into the enclosed slot in the axial direction, wherein the system array and the mating array engage each other along a mating zone (390, 391, 593, 966) within the enclosed slot, the mating zone extending essentially parallel to the centerline, and the receptacle connector having a mating mechanism (560, 993) including an actuator (564, 568, 995) and a cam plate (562, 566, 994) that are operably engaged with each other, the cam plate being positioned side-by-side and forming a slidable interface with the actuator, the cam plate including ramps (570, 996) and the actuator including recesses (572, 997) that receive the ramps, wherein the electrical contacts of the system array of the printed circuit are movable, as a group, in a radial direction that is perpendicular to the centerlinc when the plug connector engages the actuator, the actuator being pushed in a mating direction of the plug connector and being operably engaged to the cam plate such that the cam plate is driven in the radial direction causing the printed circuit to move towards the enclosed slot.