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Chapter 10
Measure Mode – Spectrum Tab
Ingress Resistance
268
DSAM Help User Guide
Rev. 001
Understanding
Ingress
Resistance
Results
The Ingress Resistance measurement mode allows for a 20 MHz
frequency span. Within each frequency, the DSAM forms and continu-
ously updates a graph with 201 frequency points. The total Ingress
Resistance frequency range extends from 88 MHz to 108 MHz.
Measurement
Information Area
The Measurement Information Area displays the current frequency
(defined by the active marker). The left side of the Measurement Infor-
mation area displays the RBW and VBW values. If Peak Hold is active,
a Peak Hold icon is displayed. The right side of the Measurement
Information area displays the active marker frequency.
Graph
As multiple updates occur, the maximum level trace changes only if
new levels exceed the levels of the current trace. A gray trace shows
you the current data when Peak Hold is on. If Peak Hold is turned on,
it ensures that the highest amplitude at each frequency point over
multiple sweeps is captured. The thick black vertical line is the active
marker; the gray vertical line is the inactive marker and does not move.
Graph Information
Bar
This bar displays the start and stop frequencies as well as dwell time.
Marker Information
Area
The Ingress Resistance measurement mode also contains an area
referred to as the Marker Information Area (area below the graph).
This area consists of the marker name, carrier frequency (in MHz), and
NOTE
Each press changes the reference setting by a single dB. The refer-
ence level range is -100 to +60 dBmV.
Figure 246
Spectrum – Ingress Resistance
Measurement
Information Area
Graph
Marker Information Area
Graph Information Bar
21128026 R001 DSAM Help User Guide.book Page 268 Thursday, February 5, 2009 2:02 PM