HP Cable Box 8591C manual Video filter

video filter

A post-detection, low-pass Elter that determines the bandwidth of the video amplifier. It is used to average or smooth a trace. Refer also to video bandwidth.

windows display mode

A display mode of the analyzers where the screen area is split into two separate displays. This allows two different frequency spans to be viewed simultaneously. The analyzer state of the two displays can be set independently.

zero span

The case in which an analyzer’s local oscillator remains Exed at a given frequency so that the analyzer becomes a fixed-tuned receiver. In

this state, the bandwidth is equal to the resolution bandwidth. Signal amplitude variations are displayed as a function of time. To avoid loss of signal information, the resolution bandwidth must be as wide as the signal bandwidth. To avoid any smoothing, the video bandwidth must be set wider than the resolution bandwidth.

zoom

A term referring to the process of looking at something more closely. This may require narrowing the resolution bandwidth or span to view a signal more closely. Or, it may mean increasing the size of the analyzer display from a partial screen to the full screen.

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