L3 NARDA PMM 9010, User Manual

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Sweep Mode Operating Instructions 4-7
4.5 Marker
Selecting this function a Marker is immediately enabled, and it appears on
the screen as a small black pointing down arrow corresponding to the highest
reading; simultaneously a small window shows up in the bottom left corner of
the screen, indicating the actual frequency and level read by the marker.
The Marker function is not a simple search for the highest readings on the
screen – it would be a useless exercise that would display a number of points
all grouped together – but it’s a true peak search that measures the degree
of variation of the signal: a peak is so classified only if it “pops-up” from the
adjacent signals with at least 5 dB difference in amplitude.
Following this criterion, if the measured signal is a flat line no peaks will be
found.
Selecting
Highest X – where X represents the maximum number of markers
found by the receiver during its sweep – few more markers are added, each
one “diamond” shaped, defined as per the previous explanation.
The maximum number of markers available is 10.
By using arrow keys it is possible to quickly move on markers from higher
amplitude (left arrow) to lower amplitude (right arrow), i.e. if the highest is
selected, pressing the right arrow key the 2
nd
highest is selected, then
pressing again the same key the 3
rd
highest and so on and so forth.
It is also possible to use the rotary knob to move from a marker to the next
one.
The marker under analysis (main marker) is a black arrow pointing down, the
others are diamond shaped.
Pressing the
Peak button the marker returns to the highest reading.
In order to make easier and faster the evaluation of the more noisy signals,
the User can now select either the
Analyzer or the Tune function, entering
respectively into a spectrum analysis of main marker position or in the
manual mode evaluation of it. To operate this two conditions please refer to
the appropriate section of this Operating Manual.
In manual mode, i.e. having selected
Tune on the main marker, it is possible
to navigate from one peak to the other just pressing the arrow keys, without
to come back to the Sweep display and remaining in manual mode.
This is another unique feature of PMM 9010 to improve the productivity of the
test lab and make easier the work of the test engineer.
The
Marker Off exits from the marker function.