Where’s the problem?

The basic function of a TDR is to test a cable to either verify its length and quality, or to identify points in the cable that are causing problems. Traditionally the user would look at the trace, in which reflections are indicated by positive or negative deviations, and place a marker on the trace spot in question for a readout of the distance to that reflection. More advanced TDRs, like the DSP TDR analyze the trace for the user, and present the detected reflection events in a table for simpler interpretation and quicker decision making.

The DSP TDR on-screen event list displays the distance to all the reflected events represented in the test trace and enables evaluation of the severity of the reflection with the return loss for each event.

How bad Is the problem?

Return loss is a measure of the severity of a reflection and can be used to determine whether an event is passing or needs further action. If there’s a problem it’s important to know not only where it is along the cable’s length, but also to know if it is severe enough to cause a problem. For example, an effective splice will still show a degree of reflection. The better the splice, the smaller the reflection.  It follows that it is important to be able to measure the reflection. Granted, an “eyeballing” of the reflection may allow a guess that any event is unimportant, but measurement precision simplifies decision making.  Therefore, a good TDR must have a return loss reading for each event (see event list above). The return loss for an event is the difference between signal reflection’s level and the original (transmitted) signal level. The higher the return loss the smaller the reflected signal and the less impact on signal transmission through the cable.

What should be done about the problem?

Documentation of TDR measurement information is a critical requirement. The test results are used to make decisions about next actions to be taken, so getting the information quickly is paramount. Not only does the measurement need to be made quickly, but the information must be relayed for decision making immediately. The DSP TDR simplifies this process by uploading the data via WiFi connection.  The uploaded information is then instantly browser accessible by others in the organization to enable an informed decision. No PC software is required.

The high quality, precise DSP TDR helps you quickly identify  where the problem is located, how bad is the return loss and what next step is required – getting the service online quickly.

Looking for a reliable DSP TDR that can address these questions and more? Find out more here.

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