Abstract: The present invention is directed toward methods and systems for providing a stackable connector system comprising a switching device configured to select a signal based on a location of a first circuit board above or below a second circuit board. A sense line may be coupled to a location signal and configured to indicate if the first circuit board is above or below the second circuit board. Additionally, a first connector, including a first conductor element, may be located on the first circuit board and a second connector, including a second conductor element, may be located on the first circuit board. An electrical connection element on the first circuit board mat connect the first conductor element to the second conductor element, wherein the location of the first conductor element in the first connector is offset relative to the location of the second conductor element in the second connector.

Abstract: A method and apparatus for measuring a gas concentration detected by a passive sampler are provided. The apparatus includes a light source which illuminates a passive sampler, a detector which detects light from the light source reflected from the passive sampler and provides an output signal, and a microprocessor which receives the output signal and calculates light absorption by the passive sampler based on the received signal.