Comtech EF Data MBT-5000 - Manual (Page 59)

MBT-5000 L-Band Up/Down Converter System MN-MBT5000
Front Panel Operation Revision 4
5–3
5.1.3 Keypad
The keypad has an auto-repeat feature. When you hold
down a key for more than one second, the key action
repeats, automatically, at the rate of 15 keystrokes per
second. This is particularly useful when editing numeric
field with many digits, such as frequency or data rate.
The keypad functions as follows:
Key Description
Use this key to display the nested menu for a selected function, or to execute (save) a
configuration change.
Use this key to cancel a configuration change that has not been executed using ENTER.
Press CLEAR to return to the previous menu screen.
(Left, Right)
Use these keys to navigate between available selections, or to move the cursor position, on
any menu screen.
(Up, Down)
Use these keys primarily to change the alphanumeric selection (i.e., numbers for configuration
data, letters for text strings) at the current cursor position, or to scroll through pre-defined
parameter settings that the MBT-5000 may provide at the current cursor position.
5.1.4 Vacuum Fluorescent Display (VFD)
The MBT-5000 features a Vacuum Fluorescent
Display (VFD). The VFD is an active display
showing two lines of 24 characters each. It
produces a blue light, the brightness of which can
be controlled by the user. Compared to a Liquid Crystal Display (LCD), it provides superior
viewing characteristics and does not suffer problems of viewing angle or contrast.
On most menu screens, a flashing solid block cursor blinks at a once-per-second rate. This
indicates the currently selected item, digit, or field. Where it might obscure the item under edit
(e.g., a numeric field), the solid block cursor automatically changes to an underline cursor.
5.1.4.1 Screen Saver
If you were to leave the operating unit displaying the same screen for weeks at a time, the VFD
could become ‘burnt’ with this image. To prevent such burn-in, a screen saver feature activates
after 1 hour. The screen saver message scrolls from right to left across the screen, and then
wraps around. The user-configurable unit label, or Circuit ID, displays on the VFD top line, while
the bottom line displays “ Press any key...”. Press any key to return to the previous
screen.