Self-contained digital data recorder, for measuring soil vibration at construction site, has separate analog channel with programmable gain and low pass filter for each seismic sensor

摘要

A self-contained digital data recorder has a data acquisition and converter card with separate channels receiving analog signals from an associated seismic sensor. Each channel has an analog signal amplifier with programmable gain and a low pass filter. A multiplexer connects the filters to a digital converter. The recorder also has a display, sound generator, removable data storage and a control unit. The unit has an operating program for setting recording conditions, recording data and indicating the end of recording. Each channel may have another filter upstream of the amplifier and a device for impedance matching with its sensor. The setting of the recording conditions includes taking several data cycles and indicating to a user if the data storage is recording them satisfactorily.