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Agilent Technologies Signal Analyzer N9030a User Manual

Page 724

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6  RLC Swept SA Measurement Front-Panel & SCPI Reference
Marker

count query. Note this result may simply mean that the first sweep after the counter turned on
has not yet completed.

Remote Command

:CALCulate:MARKer[1]|2|...12:FCOunt:X?

Notes

This query does NOT cause the specified marker to become selected.

Initial S/W Revision

Prior to A.02.00

Understanding the Marker Counter

See

"Counting Off-screen Markers" on page 724

.

See

"Delta Marker" on page 724

.

See

"Fixed Markers" on page 725

.

See

"More Information on "Counter"" on page 725

.

Using the internal counter we can count the frequency of a marker, but we cannot count while we
are actually sweeping. So, once we are done with a sweep, we move to the selected marker
frequency and count that frequency. Then, if the marker is a Delta marker, the count is also taken
for its reference marker. The count is actually performed by moving the LO to the frequency (or
frequencies in the case of a delta marker) we wish to count. The count is executed on a marker by
marker basis and no further count is taken until after the next sweep (even if the marker moves
before another sweep has completed).

The Marker Count is taken by tuning the instrument to the frequency of the marker and counting
the IF, with the instrument not sweeping. The count is adjusted for display by adding or
subtracting it (as appropriate) from the LO frequency, so that you see a count that represents the
signal frequency. This is true even if External Mixing is on. Since all this happens between
sweeps, you never see the instrument retuning to do the counts.

If you wish to see the entered frequency of a counted marker it will appear in the active function
area when that marker is selected (for Fixed markers, you have to press the Marker, Fixed key to
select Fixed markers and then press it a second time to view or adjust the x or y marker values).

Counting Off-screen Markers

If the selected marker is off the X-axis the instrument can still be tuned to the marker (unless it is
outside the current range of the instrument), so the count can still be displayed. This means you
can see a count for an off-screen marker even though there may be no valid Y-value for the
marker. If the marker frequency is outside the range of the instrument, the display will show three
dashes in the count block (---), and not a number is returned to a SCPI count query.

Delta Marker

When a Delta Marker is selected while Marker Count is on:

724

Remote Language Compatibility Measurement Application Reference