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View live spectrum capture
Last Updated: July 07, 2026

If another user has started an upstream spectrum capture, you can not start a second one, but you can view the on-going capture. Viewing an on-going capture allows you to receive FFT (Fast Fourier Transform) data in real-time, but you are not be able to pause, stop, or extend the live session.

To view an on-going capture, click OK when you receive the following message:
Active Capture in Progress pop up. Text reads, "Another user has initiated a capture either on this slot or port. Would you like to view the capture?" You can select Cancel to exit, or OK to join the capture.

Once you choose to view the on-going capture, you can change settings that update your display of the capture, but not the actual capture parameters. Settings you can change while viewing a capture are:

  • Latest
  • Peak Hold
  • Average
  • Markers

All other settings are unmodifiable and grayed out.

Once you are connected to an on-going capture, a banner is displayed.
Banner image. The text reads: Live Capture - You are watching a live capture started by user: admin.

To end your viewing of the capture, simply navigate to another tab in Spectrum Capture, or another application on the user interface. If the capture is stopped by the originator, or if time expires, viewers are notified, and the capture data is cleared when you acknowledge the end of the capture. A new capture can be created at that time by any user.

NOTE: For the E6000 CER, the hardware does not allow for more than one capture per slot. If a capture is active on a slot, other users are prevented from starting or viewing captures on a different port of that slot, and see an error message similar to the following:
Error dialog box. Title:Active Capture in Progress. Text: A live capture is in progress on this slot on channel <channel #> created by user: <username> The hardware prevents another capture on the same slot.
This is consistent with the capture functionality described in Table 1.

The maximum number of viewers is governed by a setting in TenantConfig for the maximum number of parallel websocket requests. Refer to ServAssure® NXT Design and Installation Guide for details on this setting.