A capsule camera system, comprising: a housing having an elongated shape and adapted to be swallowed; a power source within the housing located at a first end of the housing, the power source comprising: at least one battery (220A, 220B, 926A, 926B); a first battery-contact pad contacting a first polarity terminal of said at least one battery (220A, 220B, 926A, 926B); a first circuit board (234, 912) comprising a second battery-contact pad contacting a second polarity terminal of said at least one battery (926A, 926B); and power-output nodes disposed on the first circuit board and facing away from the first end of the housing, which power-output nodes are on a plane perpendicular to a longitudinal axis of the housing; a capsule sub-system within the housing positioned further from the first end than the power source, the capsule sub-system comprising: a light source; a camera for capturing a digital image of a scene illuminated by the light source; and a second circuit board (236, 914), on which the light source is disposed; an electrical interconnect (140, 240, 352, 910) between the power source and the capsule sub-system connecting the second circuit board (236, 914) to the power-output nodes, wherein the electrical interconnect (140, 240, 352, 910) comprises electrical contacts at one or both ends, wherein electrical power is supplied to the capsule sub-system from the power source through the electrical interconnect (140, 240, 352, 910), and wherein at least one of the electrical contacts, either between the electrical interconnect (140, 240, 352, 910) and the power-output nodes or between the electrical interconnect (140, 240, 352, 910) and the second circuit board (236, 914), is a pressure contact. a housing having an elongated shape and adapted to be swallowed; a power source within the housing located at a first end of the housing, the power source comprising: at least one battery (220A, 220B, 926A, 926B); a first battery-contact pad contacting a first polarity terminal of said at least one battery (220A, 220B, 926A, 926B); a first circuit board (234, 912) comprising a second battery-contact pad contacting a second polarity terminal of said at least one battery (926A, 926B); and power-output nodes disposed on the first circuit board and facing away from the first end of the housing, which power-output nodes are on a plane perpendicular to a longitudinal axis of the housing; at least one battery (220A, 220B, 926A, 926B); a first battery-contact pad contacting a first polarity terminal of said at least one battery (220A, 220B, 926A, 926B); a first circuit board (234, 912) comprising a second battery-contact pad contacting a second polarity terminal of said at least one battery (926A, 926B); and power-output nodes disposed on the first circuit board and facing away from the first end of the housing, which power-output nodes are on a plane perpendicular to a longitudinal axis of the housing; a capsule sub-system within the housing positioned further from the first end than the power source, the capsule sub-system comprising: a light source; a camera for capturing a digital image of a scene illuminated by the light source; and a second circuit board (236, 914), on which the light source is disposed; a light source; a camera for capturing a digital image of a scene illuminated by the light source; and a second circuit board (236, 914), on which the light source is disposed; an electrical interconnect (140, 240, 352, 910) between the power source and the capsule sub-system connecting the second circuit board (236, 914) to the power-output nodes, wherein the electrical interconnect (140, 240, 352, 910) comprises electrical contacts at one or both ends, wherein electrical power is supplied to the capsule sub-system from the power source through the electrical interconnect (140, 240, 352, 910), and wherein at least one of the electrical contacts, either between the electrical interconnect (140, 240, 352, 910) and the power-output nodes or between the electrical interconnect (140, 240, 352, 910) and the second circuit board (236, 914), is a pressure contact.