Sea Tel 9497B-21, Installation And Operation Manual

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9497B-21 C/Ku-Band TVRO Maintenance and Troubleshooting
7-5
7.5.2.
The RS-232, RS-422, or RS-485 (depending on configuration) Radio M&C signals pass from the BDE computer
through the RF M&C port of the base modem and are modulated and demodulated. These M&C signals are
diplexed with the Pedestal M&C signals before passing through to the above decks modem. The Pedestal
modem then converts the RF Signal back to RS-232/422/485, before routing to the M&C port of the above
decks radio equipment via an interface cable.
Radio M&C
7.5.3.
There are four base frequencies used in the 400MHz FSK modem assemblies:
Channel Identification
•
The BDE Modem Transmits Pedestal M&C at 452.5 MHz
•
The BDE Modem Transmits Radio M&C at 447.5 MHz
•
The ADE Modem Transmits Pedestal M&C at 465.0 MHz
•
The ADE Modem Transmits Radio M&C at 460.0 MHz
Figure 7 ADE Modem Transmit Frequency Markers
Figure 8 BDE Modem Transmit Frequency Markers