Measurement Functions | 3M™ Dynatel™ Advanced Modular System 965AMS |
DSL>DSL Impulse Noise>Application Notes
Since impulse hits, noise and other power related interference can fluctuate during the day you have the option of measuring three different levels. If you traditionally measure Impulse hits at a threshold of 40 dBrn, then select a count threshold of 32 and a spread of 2 dB, then you will be able to see any hits that exceed 32, 36 or 40. Although this circuit will pass at 40, you will be able to see if there is noise just under the threshold that can appear later with a change in power usage or plant conditions.
Selected a spread of 4 dB and a threshold of 32 would allow you to count hits that exceed 32, 36 and 40.
Check with your DSLAM vendor regarding excessive hits for a circuit. Different DLSAM vendors have settings to make use of buffers (dynamic memory) to compensate for errors that can be caused by impulse noise.
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