Comtech EF Data CDM-550T, Manual

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Physical Description CDM-550T Satellite Modem
4–2 Rev. 1.3
4.1 Front Panel
On the front panel of the unit is the Vacuum Fluorescent Display (VFD), keypad, and
eight LED indicators. The user enters data via the keypad, and messages are displayed on
the VFD. The LEDs indicate, in a summary fashion, the status of the unit.
The Vacuum Fluorescent Display (VFD) is an active display showing 2 lines, each of 24
characters. It produces a blue light, the brightness of which can be controlled by the user.
It has greatly superior viewing characteristics compared to a Liquid Crystal Display
(LCD), and does not suffer problems of viewing angle or contrast.
The keypad comprises six individual keyswitches, mounted directly behind a fully sealed
membrane overlay. They have a positive ‘click’ action, which provides the user with
tactile feedback. These six switches are identified as UP ARROW, DOWN ARROW,
RIGHT ARROW, LEFT ARROW, ENTER and CLEAR.
The functions of these keys are described in the ‘Front Panel Operation’ section.
There are 8 LED indicators. The functions of these indicators are shown in the Table 4-1
below:
Table 4-1. Front Panel LED Indicators
LED Color Condition
Red A Unit Fault exists (Example: PSU fault)
Orange No Unit Faults, but a Traffic Fault exists
Unit
Status
***
Green No Unit Faults, or Traffic Faults
Green No Tx Traffic Faults Transmit
Traffic
***
Off A Tx Traffic fault exists OR the Tx Carrier is in OFF state
Green No Rx Traffic Faults (demod and Viterbi decoder are locked, everything is OK) Receive
Traffic
***
Off An Rx Traffic fault exists (the demod may still be OK)
Green The Unit is On Line, and carrying traffic
On line
Off The Unit is Off Line (standby) - forced by externally connected 1:1 or 1:N redundancy system
Orange
There is a Stored Event in the log, which can be viewed from the front panel, or retrieved via the
remote control interface Stored Event
Off There are no Stored Events
Orange The Unit is in Remote Mode - local monitoring is possible, but no local control
Remote
Off The Unit is in Local Mode - remote monitoring is possible, but no remote control
Orange Framing on, EDMAC on, and unit defined as Slave EDMAC
Mode
Off Either no EDMAC, EDMAC Master, or Transparent mode is selected
Orange A Test Mode is selected (Example: IF Loopback)
Test Mode
Off There is no Test Mode currently selected
*** IMPORTANT NOTE REGARDING THE REATIONSHIP BETWEEN
FRONT PANEL LEDS AND ALARM RELAYS:
In general, the Alarm relay state will reflect the state of the Front Panel LEDs. For
instance, if the Unit Status LED is red, the Unit Alarm relay will be active, etc.
The one exception is the Transmit Traffic relay. This will only be activated if a
Transmit Traffic Fault exists – it does not reflect the state of the TX carrier.