HP Cable Box 8591C manual Spectrum Analyzer Mode Key Descriptions

Spectrum Analyzer Mode Key Descriptions

Spectrum Analyzer Mode Functions

adds an offset value to the displayed reference level. Offsets are entered by using the number/units keypad. Entering an offset does not affect the trace or the attenuation value. Reference-level offsets are used when gain or loss occurs between a device under test and the -analyzer input. Thus, the signal level measured by the analyzer is the level at the input of an external amplitude-conversion device. When an amplitude offset is entered, its value is displayed on the left side of the screen (as opposed to frequency offsets which are displayed at the bottom of the screen). To eliminate

an offset, press REF LVL OFFSET , 0 C--dBmV] or (+dBmV]. Pressing (j-1 also sets the offset to zero. Reference-level offsets are entered using the numeric keypad. See also the EXTERNAL PREAMPG softkey description.

Front-Panel Key Access (j-1

changes the analyzer 3 dB resolution bandwidth. As the resolution bandwidth is decreased, the sweep time is increased to maintain amplitude calibration. Resolution bandwidth is also related to span. As span is decreased, the resolution bandwidth is decreased. A “#” mark appears next to RES BW on the screen to indicate that it is not coupled. To recouple the resolution bandwidth, press

RES BW AUTO MAN so that AUTO is underlined. The resolution bandwidth can be changed using the step keys, the knob, or the numeric keypad.

Front-Panel Key Access [AUTO COUPLE] or m

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