Wegener UNITY4000, Instruction Manual

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3-5 UTY4000-003
selected stream is a stereo or dual-mono signal. It may be routed to the L and R connections in a
specific relationship to the original audio connections at the uplink MPEG encoder unit:
Table 3-3. Audio Handling
Stereo Original encoder L and R routed to corresponding L and R outputs on
IRD
Reverse Stereo Original encoder L routes to IRD R output, while original R routes to
the L output
1 on both* Original encoder L is routed to both L and R outputs on IRD
2 on both* Original encoder R is routed to both L and R outputs on IRD
* Originally, left “channels” were designated “1” and right as “2”. Now “channel” designates
the selected audio program by PID.
3.6 SOURCES OF CONTROL
The IRD can be controlled via COMPEL™, terminal, modem, DIP switches, and Display / push
buttons. Each of these methods of control is explained in the following sections, but you should
see the COMPEL manual for a complete explanation of the COMPEL system.
3.6.1 COMPEL™
The COMPEL command stream from the uplink is usually the unit’s primary source of control.
This asynchronous stream is mux’ed into the aggregate MPEG data stream at the uplink. An
IRD can also accept a local COMPEL command stream from its serial port if enabled by the
satellite program provider. However, it can only process one of these streams at any given time.
See the COMPEL Manual for a complete explanation of the COMPEL system.
3.6.2 Terminal
The terminal command interface can be accessed by setting serial port 2 “device” to “Terminal”
(using front panel control). You may then access the terminal commands if you have a terminal
installed. These commands appear on a help screen and are documented in Appendix A of this
manual. With the exception of the “R” and “H” commands, they are only available if local
control is enabled.
3.6.3 Modem
The modem command interface is similar to the terminal interface. That is, it does not utilize
special handshaking or special control characters for this interface, and only supports auto-
answer modems. In fact, the IRD does not distinguish between an attached terminal and a
modem. To access the modem command interface, the serial port 2 “device” must be set to
“Modem” (using front panel control). To access user commands, the user must enter the correct
password at the prompt. The user then retains access until (1) the “OH” command is received, or
(2) 10 minutes passes with no user input. As is the case for the terminal, the user commands are
restricted when local control is disabled.