... , etc, especially for long time unattended testing System consists of data acquisition device, zero time receiver and built-in geophone. Reflection ... before lithium cell, voltage after lithium cell, sampling point data.21Length of Data File Name, 8-Bit: The first 6 digits for ... , which can be used for WINXP system23 Adopt USB 2.0 interface for data transmission with PC24 With PDA, easy for field work ...