Agilent Technologies E4440A Saw User Manual


 
Chapter 3 181
Instrument Functions: M - O
Marker
Instrument Functions: M - O
3.1.3 Delta
Sets the control mode for the selected marker to Delta (see “Marker” on page 177). In Delta
mode the display shows the difference between the active (Delta) marker and a reference
marker. When
Delta mode is selected the reference marker is placed at the current marker
position. If the marker is
OFF both the active marker and the reference marker are placed
at the center of the display. The amplitude and frequency (or time) of the first marker is
fixed. The marker number is indicated above the delta marker, and the same number is
indicated with an R (for example, 1R) above the reference marker. You can adjust the trace
point of the active delta marker. Annotation in the active function block and in the
upper-right corner of the display indicates the frequency or time difference and amplitude
difference of the two markers. If marker noise is set to On while using Delta and the noise
marker is placed on the noise floor, the marker readout displays signal to noise.
Selecting
Delta while already in Delta mode causes the reference marker to be reset to the
current active () marker position, enabling you to make delta measurements from
differing reference points without having to turn off the markers and begin again. Pressing
Marker Normal moves the Reference Marker to the Delta Marker position and turns off
Delta Marker.
The amplitude of the reference marker is fixed. In non-zero spans the frequency of the
reference marker is fixed. If the center frequency of the analyzer is changed such that the
reference marker is off the screen, an arrow will appear with the marker number at the
left or the right side of the display. This indicates where the trace point is for the reference
marker.
In
Zero Span the reference marker remains fixed at the trace point on which it was placed.
Also, changing Center Frequency does not move the reference marker while in Zero Span.
The markers will be turned off if the scale type is changed between log and linear.
Key Path:
Marker
Remote Command:
See “Marker” on page 177 for the mode command.
Example: CALC:MARK4:MODE DELT selects marker 4 as a delta marker and places a
reference marker at the marker 4 position. If marker 4 is OFF it places
both the active and the reference markers at the center of the display.
3.1.4 Delta Pair
Sets the control mode for the selected marker to Delta Pair (see “Marker” on page 177). In
Delta Pair mode the display shows the difference between the delta marker and a reference
marker and enables you to adjust both the
Ref (start) and Delta (stop) markers
independently. After you turn on the delta Pair function, pressing the key again toggles
between the two markers you are controlling. When Ref is underlined you are controlling
the reference marker. When is underlined you are controlling the delta marker. The start
marker number is indicated with a number and an R above the marker (for example, 1R)
and the delta marker is indicated with a marker number.