Time Domain Transmissometer Module STDT-65

Overview & Features

Time domain transmission measurement module STDT-65 (extension for Sequid time domain reflectometer STDR-65)

  • No extra casing and cables required
  • 65ps sampling gate according to STDR-65
  • Fully integrated & synchronized with base device STDR-65
  • No additional latency
  • Fully integrated ESD protection module (optional)
  • Full automatic temperature compensation

Product Specification

Fully Integrated System

The transmission module STDT-65 is the optimal extension for the time-domain reflectometer STDR-65 for performing transmission measurements. The STDT-65 is fully integrated into the STDR-65 and therefore no further external components like cables and power dividers are necessary. The STDR-65 and the STDT-65 are well matched to each other, thus the same excellent jitter performance (Jrms<500fs) ensures that the high standards of the STDR-65 with regard to amplitude-, time-base- and temperature stability are reached. Furthermore, the integration of the STDT-65 has no influence on the acquisition time, because the signal sampling of the transmission module is optimally integrated in the standard data acquisition of the STDR-65 and is performed in parallel within the same cycle, thus no further latency is introduced.

System Extension

In most applications a traditional TDR step-signal is a suitable choice for solving a variety of measurement tasks. Nevertheless, in practice many scenarios are thinkable where a measurement signal different from the step-signal may be advantageous. Many TDR instruments lack the possibility to overcome these problems. By applying the STDR/T-65 system in combination with external component (e.g. pulse-former), a user-defined shape of the measurement signal can be applied. The SMAS®-components are optimally matched in the STDR/T-65 system and therefore can be utilized without further adaptations. In case the user already has an existing pulse-forming system, we would be glad to support you with the adaption to the Sequid equipment.

Mechanical Specifications

The STDT-65 is fully integrated into the STDR-65, thus a completely enclosed system is provided. Thus the same high mechanical protection class is available and the practical and compact design of the STDR-65 is kept.


  • RF cables
  • Thru calibration standard

Fields of Application

  • TDT applications
  • Moisture measurement
  • Fault detection
  • Testing of electrical connections
  • Scattering parameter measurements (S21)

Further Information

Further Information about time domain reflectometry (TDR) moisture measurement you will find in our download area.