Comtech EF Data CDM-550T, Manual

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Installation CDM-550T Satellite Modem
2–2 Rev. 1.3
Note that the CDM-550T is very light - under 7 lbs (3.2 kgs), and very short - 12 ins (305
mm). For this reason, it has not been designed to have rack slides mounted to the side of
the chassis. However, Comtech EFData recommends that some method of support within
the rack should be employed, such as rack shelves. If there is any doubt, please consult
the factory.
2.3 Configuration
There are no internal jumpers to configure, no interface cards to install, and no other
options to install. All configuration is carried out entirely in software. The unit should
first be configured locally, using the front panel keypad and display. The unit will ship
with a default 64 kbps, QPSK, Rate 1/2 configuration. Please refer to the ‘FRONT
PANEL OPERATION’ section for details on how to fully configure the unit for the
desired operating parameters.
The auto-sensing AC power supply does not require any adjustments. Simply plug in the
supplied line cord, and turn on the switch on the rear panel.
2.4 Select Internal IF Loop
Correct operation of the unit may be verified rapidly, without the need for externally
connected equipment. From the top level menu, select TEST, then IF LOOP (refer to the
‘FRONT PANEL OPERATION’ section) The demod should synchronize, and the green
RECEIVE TRAFFIC LED should illuminate. If the unit does not pass this test, call the
factory for assistance.
2.5 Connect External Cables
Having verified correct operation in IF loop, enter the desired configuration, and proceed
to connect all external cables. If difficulties occur, please call the factory for assistance.
Please note that the modulator gives an output power level in the range 0 to -20 dBm, and
the demodulator expects to see a signal in the range -30 to -60 dBm.
FREQUENTLY ASKED QUESTION - Optimum input level:
Adjust the input level to the demodulator so that the AGC value
displayed on the RX PARAMETERS screen reads between 90
and 95.