HP ESA-L1500A, Руководство пользователя и калибровки

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Chapter 4 83
Front-Panel Key Reference
Frequency
Frequency
Frequency
activates the center frequency function, and accesses the
menu of frequency functions. The center frequency, or start and stop
frequency values appear below the graticule on the display.
Although the spectrum analyzer allows entry of frequencies greater
than the specified frequency range, using frequencies greater than the
frequency span of the spectrum analyzer is not recommended
NOTE
When changing both the center frequency and the span, change the
frequency first since the span can be limited by the frequency value.
Center Freq
activates the center-frequency function which allows you to select a
frequency to be centered on the display. Key Access:
Frequency
Start Freq
sets the frequency at the left side of the graticule. The left and right
sides of the graticule correspond to the start and stop frequencies.
When these frequencies are activated, their values are displayed below
the graticule in place of center frequency and span.
Key Access:
Frequency
Stop Freq
sets the frequency at the right side of the graticule. The left and right
sides of the graticule correspond to the start and stop frequencies.
When these frequencies are activated, their values are displayed below
the graticule in place of center frequency and span.
Key Access:
Frequency
CF Step Auto Man
changes the step size for the center-frequency function. Once a step size
has been selected and the center frequency function is activated, the
step keys change center frequency by the step-size value. The step size
function is useful for finding harmonics and sidebands beyond the
spectrum analyzers current frequency span. When auto-coupled, the
center frequency step size is set to one graticule (10 percent of the
span). Key Access:
Frequency
Freq Offset
allows the user to input a frequency offset value that is added to the
frequency readout, to account for frequency conversions external to the
spectrum analyzer. Offset entries are added to all frequency readouts
including marker, start frequency, and stop frequency. Entering an
offset does not affect the trace. Offsets are not added to the span.
Frequency offsets are entered using the numeric keypad.
When a frequency offset is entered, its value appears on the bottom of
the display (as opposed to reference level offsets, which appear on the
left side of the display). To eliminate an offset, press
Freq Offset
,
0
, and
Enter
. Pressing
Preset
also sets the offset to zero. Key Access:
Frequency