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1256E User Manual
Using the Front-Panel Controls 3-2
Racal Instruments
©
2002
Front Panel
The front-panel controls consist of four keypad switches
(pushbuttons), a four-line alphanumeric display, and a rotary
knob (see
Figure 3-1, Front-Panel Controls
).
The display contains four alphanumeric lines of text. To the left of
the display are the four keys, each corresponding to one line of
the display. The keys select the display line to work with. After
selecting a display line, the user may rotate the knob to change
the parameter indicated on the selected line.
Figure 3-1, Front-Panel Controls
Understanding
the Hierarchical
Menu
The 1256 uses a multiple-level, hierarchical menu tree. To help
the user visualize the menu tree, the menu is limited to four
levels. Each hierarchical level is shown on its own line on the
front-panel display. The top line shows the top level.
The user begins by selecting a general type of function on line 1
(top line). Then, on line 2, the 1256 displays choices that are
more specific to the general function that was selected on line 1.
After the user selects from the choices on line 2, the 1256 shows
related parameters on line 3. Once the user chooses a parameter
from line 3, the 1256 displays the current status, or value, of this
parameter on line 4. On line 4, the user may choose from among
different values for the parameter.
For example, suppose slot 3 of the 1256 contains a Model
1260-120 plug-in. To close relay channel 2 on this plug-in, the
user proceeds as follows:
1256
SWITCHING SYSTEM
Display
Keypad
i h
Speaker
Knob