L3 NARDA PMM 9010, User Manual

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10-28 PMM 9030 Frequency Extension
10.12.4 Display
Pressing the
Display button it is possible to set two parameters: the
visualized Dynamic range (chosen between 80, 100 and 120dB) and the
Reference Level, that can be increased or reduced by steps of 5dB within
the range +55 dB
µ
V to 90 dB
µ
V (-50 to - 15 dBm).
10.12.5 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 a certain amount of dBs.
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
(left arrow) to lower (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 9030 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.