ComStream CM601, Инструкция по установке и эксплуатации

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7-4 Configuration Examples
CM601 Configuration with Two Data Interfaces
This configuration consists of:
Standard CM601 with the following cards:
M&C
Modem card
I/O in slot 1
User data rate is 9.6 kbps
BPSK
Sequential rate 1/2 decoding
Transmit timing
Provided by the DTE
Transmit clock and data sent to the I/O card in slot 1will be used for the
transmit portion
Receive data will be output from the I/O port on the modem card in slot 5.
Filtering is ComStream closed-network
The IF frequencies used in this example are representative only. You must
calculate the actual IF frequencies based on the RF equipment used and the
frequencies assigned by the satellite provider prior to any actual RF transmissions
To configure the system:
1. Ensure that the Test Mode LED on the front panel is not illuminated. If it is
illuminated, perform the following steps:
a. Turn all loopbacks off, enter
LB 0
.
b. Turn pure carrier mode off, enter PC 0 .
c. Turn the internal BERT off for each I/O card and the modem card. This is
done by preceding the command with the slot number followed by a
colon:
• Enter 1:BEN 0 .
• Enter
5:BEN 0
.
2. Configure the modem for the described I/O selection and timing mode noted
in the assumptions:
a. Select the I/O card in slot 1for TD and TT (if not data rate restricted),
enter
TIO 1 .
b. Select the modem card in slot 5 for RD and RT, enter
RIO 0
.
c. Select DTE to provide transmit timing, enter
MB 1
.
The modulator latches data on the falling edge of the TT clock when MB
is set to 1, and the state of the ML command will be ignored.