← Back to Articles
Perform upstream impulse noise capture
Last Updated: July 07, 2026
Upstream impulse noise capture is supported starting from E6000 CER firmware version 8. Configuration changes are required on the CMTS side using the CLI. SNMP-based configuration is not supported. This is a service-impacting event; the SC-QAM upstream channel being used for capture must be in measurement mode and removed from service.
NOTE:
  • Impulse noise capture does not require a separate license; it is available as part of the Upstream Spectrum Capture application. However, your user profile must be assigned to a group that contains the Impulse Noise Capture permission before it can be accessed in the ServAssure NXT user interface.
  • When working with an E6000 CER CMTS, use compatibility mode while running an impulse noise capture to obtain the correct timeIQ data. Refer to "Issues specific to compatible devices and equipment" in ServAssure® NXT Release Notes for more information.
  1. Make sure your user profile is assigned to a group containing the Impulse Noise permission is. See the ServAssure® NXT Administration Guide for details.
  2. Make sure the upstream channel that the capture is being performed on has been removed from service.
  3. Open the US Spectrum Analyzer application; see Access upstream spectrum analyzer.
  4. Click the Test tab.
  5. Enter a search term for a channel (see Search channel).
  6. Set the center frequency.
  7. Specify a passband width.
    NOTE: Center frequency and passband width cannot be changed while a capture is occurring.
  8. Specify start and end triggers for the beginning and end of the capture.
  9. (Optional): Specify a custom range for the X and Y axes, as described in Set up X and Y axes.
  10. Click Play to start the capture.

    You can also Stop the capture before the configured duration or 60 seconds. All data is saved.