4-42
graph. These parameters include Ref Level and Scale. The reference
level is the midpoint level displayed on the graph. The Ref Level
can be adjusted using the cursor keys or by entering a numeric value
followed by the
ENTER
key.
The scale parameter (1,2,5, & 10 dB/Div) can only be adjusted with
the cursor keys. For example, if the reference level was set at 2 dB
and the scale was set at 5 dB/div the first horizontal grid line above
the center would be equal to 7 dB. An
Auto Scale
soft key will
automatically set the reference level for an optimum sweep display.
The
FCN
+
Scale
key will also automatically scale the sweep display.
Press the
LVL
soft key to return to main sweep display.
Marker Adjustments
The sweep display includes horizontal and vertical markers. The
vertical markers appear on the graph at all times. The vertical
markers are labeled M1 & M2. M1 is always to the left of M2. The
markers cannot be adjusted to crossover each other. The vertical
markers are adjusted using the top two sets of soft keys correspond-
ing to the displayed arrows. The horizontal markers are turned on
and off in the Sweep setup screen. The horizontal markers are not
adjustable, they automatically track the max and min values in the
area of the graph between the vertical markers. The numeric value
for Max/Min appears below the sweep graph. This is the maximum
level minus the minimum level for the area of the graph between
(and including) the vertical markers.
Note the "M1" and "M2" indicators to the left of the marker frequen-
cies below the graph. The inverse highlighting of the "M2" indicator
means that marker #2 is currently active. There can be only one
active marker at a time. This is the marker that was last adjusted
using the left/right arrow soft keys. The frequency of the active
marker can be entered directly using numeric keys. The numerals
appear on the screen as they are entered. The location of the entry
field corresponds to the marker being set (M1 or M2). When the edit
box is being displayed, neither marker is active.
Limit Adjustments
A
LIM
(limits) soft key is used to turn the limits function on/off,
