- Simultaneous acquisition of MR signals from array coils provides improved signal-to-noise ratio in MR imaging. RF coil arrays of up to four channels are commonly used, and emerging applications such as functional imaging and MR microscopy could benefit from the use of even larger arrays. This paper extends previous work by the authors in time-domain multiplexing (TDM) of MR receivers to enable simultaneous acquisition from arrays of sixteen or more elements. A modular TDM unit is developed, based upon a printed circuit four channel multiplexer board. Using this modular system a sixteen channel multiplexer has been developed and tested.