The PC-TDR software is compatible with the SDM8X50 multiplexer, but the non-latching relays may cause issues. When PC-TDR (version 2.08 and lower) advances to a multiplexer terminal, it sends one command to the multiplexer. With the older SDMX50-series multiplexers, one command was sufficient because the relays latched. The non-latching relays on the SDM8X50 release 30 seconds after the command is sent, which results in a loss of connection between the sensor on that terminal and the TDR100. To latch again for a good reading, it is necessary to manually force PC-TDR to go to a different SDM8X50 terminal and then back to the terminal of interest. The continuous waveform function should not be used with the SDM8X50. These known issues will be addressed in the next version of the PC-TDR software.