Measurement Functions

3M™ Dynatel™ Advanced Modular System 965AMS

DSL>DSL Loss>Application Notes

DSL Loss measures the signal lost from a tone transmitter (965AMS tester, 3MDynatelFar End Device (FED) or other capable device) to the measuring 965AMS.

High loss is an indication of:

1.A loop that is too long for the potential service.

2.Bridge tap.

To get a complete picture of loss, it is recommended that you use a FED device that will generate a sweep of frequency for the service type. The sweep will indicate either a good circuit, high loss or dips in the reading can be an indication of bridge tap. The image below is a sweep that was performed with a 965AMS tester, a 3MDynatelFar End Device FED II and the selected service was ADSL2.

Look at the before and after for these two readings. When the bridge tap is removed then the slope no longer displays frequency dips.

With 500 feet of bridge tap

With bridge tap removed

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3M 965AMS manual Dsldsl LossApplication Notes