A sensor device comprises at least two sensors at the end of a shaft (such as a guidewire or catheter). One sensor uses signals in a first frequency range and a first voltage range and the other sensor uses signals in a second frequency range different to the first frequency range and a second voltage range different to the first voltage range. The first sensor is shorted based on frequency analysis, thereby to prevent the first sensor being exposed to signals associated with the second sensor. This enables the two sensors to be driven by the same shared pair of wires along the shaft, with automatic selection of the suitable sensor.
