A hydraulic weighing machine includes a base, a weighing platform, an expandable bag, an upright stand, and a vertically extending weight scale. Levels of ambient light andor reflected light can be detected by detectors and transmitted to a processing unit. The second transmission filter and the second reception filter are embedded in the circuit substrate in locations that overlap at least a part of a projection region that is formed by projecting the first duplexer in a thickness direction of the circuit substrate. Moreover, the chip supporting member interposed between the chip and die pad provides greater flexibility for mounting variously sized or shaped chips on the die pad without having to use chips corresponding to profile of the die pad. An MMT processor calculates the rising edges of the direct path component of the received signal, selects the accumulator whose content correspond to a reference value related to the pulse height of the direct path component and compares the timing of the samples in that accumulator with the timing of the reference value on a reference pulse.