HP ESA-L1500A, Руководство пользователя и калибровки

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Chapter 4 85
Front-Panel Key Reference
Marker
Marker
Marker
accesses the marker control keys which select the type and
number of markers and turn them on and off. Markers are
diamond-shaped characters that identify points of traces and allow the
traces to be manipulated and controlled on the display. Up to four
markers may appear on the display simultaneously; only one can be
controlled at a time. The marker that is controlled is called the “active”
marker. Pressing
Marker
activates the
Marker Normal
softkey.
Marker Normal
activates a single frequency marker at the center frequency on the
active trace if a marker is not already displayed. If a marker is
displayed before the
Marker Normal
function is enabled, the marker is
enabled at the position of the currently selected marker. Use the data
controls to position the marker. Annotation in the active function block
and in the upper-right corner indicates the frequency and amplitude of
the marker. The marker stays on the trace at the horizontal screen
position where it was left unless
Signal Track On Off
, or a “marker to”
softkey function (such as
Mkr
→
CF
,
Mkr
→
RL
,
Mkr
→
CF STEP
,
Mkr
∆
Span
,
or
Min Search
) is selected. Pressing
Marker Normal
turns off the
marker-delta function. Key Access:
Marker
Marker D
activates a second marker at the position of the first marker. (If no
marker is present, two markers appear at the center of the display.) The
amplitude and frequency of the first marker is fixed, and the second
marker is under your control. Annotation in the active function block
and in the upper-right corner of the display indicates the frequency and
amplitude differences between the two markers. The delta marker
readout will be incorrect if the scale type is changed between log and
linear.
NOTE
If there are already four markers when
Marker
∆ is pressed, a nonactive
marker disappears, the active marker becomes a reference marker, and
the delta marker becomes the active marker. If marker noise is turned
on while using
Marker
∆ and the noise marker si placed on the noise
floor, the marker readout displays signal-to-noise.
Key Access:
Marker
Select Marker
1 2 3 4
selects one of the four possible markers. A marker can be turned on
once it is selected. A marker that has already been turned on will
become active when it is selected. If a marker has already been turned
on and assigned to a specific trace it will become active on that trace
and the
Marker Trace Auto A B C
softkey will have the appropriate trace
letter underlined. Key Access:
Marker