Article · January 2000 citations 16 reads 1,575 1

SOFTWARE AND DATA REDUCTION

SP232
SP232 is an MS-DOS computer program developed by Tektronix to digitize and store 1502B/C cable signatures. The format is ASCII and can be read and printed by the SP232 software, or modified and plotted with a spreadsheet such as Excel.


Some laptops, particularly newer models have trouble communicating with the 1502 using SP232. In this case, a lower averaging setting, say four, often solves the problem. Sometimes it is necessary to use a different computer before communication can be achieved. A good solution is to use an old 386 or 486 laptop running MS-DOS or Windows 3.1.


PCTDR100
PCTDR100 was written by Campbell Scientific, Inc. to view signatures from the new TDR100. It is Windows™ 98/NT compatible and easy to use. It has many features and can be even step through a multiplexer to which several cables are attached. Cable signature output is in tabular ASCII format and also can be plotted in a spreadsheet.


TDRPlot2000^©
TDRPlot2000^© (www.kanegeotech.com) is used for plotting and comparing TDR cable signatures from 1502B/C testers using SP232, Tektronix1502B/CS remote testers, TDR100 testers using PCTDR100, and remote TDR100 testers. TDRPlot2000^© is a preprocessor for DPLOT95,a Windows™-based scientific plotting program developed bythe U.S.ArmyCorps of Engineers Waterways Experiment Station (www.smd4d.wes.army.mil). The program converts desired TDR signatures to DPLOT95 format and automatically plots the signatures. The advantage to this approach is that DPLOT95 allows the flexibility to manipulate and compare multiple TDR signature on one plot. Figure 2 is an example of a signature plotted using TDRPlot2000^© and DPLOT95.

SUMMARY

TDR is becoming a widely accepted instrumentation method for monitoring slope movement. It uses an inexpensive coaxial cable as a sensor, and works like radar to locate shear planes or zones of deformation in a slope. In the right conditions, it has many advantages over conventional probe inclinometers, although it is not always the best solution. One outstanding advantage of TDR is that its digital signal is readily compatible to remote applications using a datalogger. Software is available to process data and produce report- quality plots.