Synchrony of physiological signals in time is essential as the correct alignment of signals allows discovery and exploration of information embedded in the interaction of signals. An example is that the ability to measure synchrony of respiratory and cardiac events as part of an assessment of cardiopulmonary interactions relies on this appropriate alignment of signal types. In many analyses, appropriate alignment of signals is assumed. In this project we built an experimental apparatus to assess the synchrony in time of commonly sampled physiological signals used in our work. The apparatus introduces a characteristic artifact across data streams allowing synchrony in time to be assessed.