1257 User Manual
Using the Front Panel Controls 3-2
EADS North America Defense
Test and Services, Inc.
©
2001
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 1257 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 function category on line 1
(top line). Then, on line 2, the 1257 displays choices that are
specific to the function selected on line 1. After the user selects
from the choices on line 2, the 1257 shows related parameters on
line 3. Once the user chooses a parameter from line 3, the 1257
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 the 1257 contains a 1260-CDS drawer. To
close relay channel 102 on this drawer, the user proceeds as
follows:
Display
Racal Instruments
Switching System
model 1257
Keypad
Knob
Speaker
