SDM8X50 Coaxial Multiplexer for TDR Systems

The SDM8X50 is a new 50 ohm, coaxial, 8:1 multiplexer for TDR100-based systems that has replaced the SDMX50-series coaxial multiplexers. The main improvement over the SDMX50 series is hermetically-sealed, non-latching mechanical relays for both the ground and signal lines of each multiplexer channel and on the lines shared internally by multiple channels.

Benefits of these relays are:

  • Quieter operation
  • No oxidation buildup—Oxidation can cause erroneous TDR readings.
  • Longer lasting—Specified for 100 x 106 operations, these relays provide 20 times more operations than provided by the SDMX50-series relays.
  • Better surge protection—Relays unlatch 30 s after receiving a channel advance command so that electrical surges are less likely to have an electrical pathway back into the TDR100 and damage the TDR100’s input diodes.