User's Manual Part 1

Table Of Contents
OPERATION 3EM21522AAAA
DTR-0200-SA-SIRIUS Issue 1, March 2008
5-2
mode prevents a remote operator from accidentally turning on the HPA from the
remote site and applying high RF level from the repeater. This could seriously injure
the technician working on the repeater at the local site and/or damage the repeater.
5.3
MODES OF OPERATION
There are two main parameter groups which determine the operating mode. They are
the Repeater Operating Mode parameter group and the Modulator Operating Mode
parameter group.
5.3.1
Repeater Operating Modes
The three repeater operating modes are Broadcast, Standby, and Manual. The
repeater’s normal operating mode is Broadcast. Under normal, no-fault, conditions if
the repeater has an AC power shut-down, upon return of power its AC power-up algo-
rithm will restore operation to the same mode of operation prior to the loss of power.
5.3.1.1
Broadcast Mode
This mode allows the repeater to transmit real signals or test signals, run all the pro-
tection loops and ALC. This is the normal operating mode for the repeater. It receives
its input signal from the satellite
, or generates a test signal, and transmits an orthog-
onal frequency division multiplexing (OFDM) signal for terrestrial broadcast. In this
mode
, the Main Controller automatically maintains all repeater functions. To operate
in the Broadcast mode, the following conditions must be met:
The repeater must be receiving an input signal and be locked to the input
stream (if the modulator is in the test mode, the VSAT satellite signal
presence is ignored).
The ALC loop must be running.
There must be good GPS signal quality (if the modulator is in the test
mode
, the GPS signal presence is ignored).
There must be no modulator alarms.
There must be no VSAT alarms (if the modulator is in the test mode, the
VSA
T satellite signal presence is ignored).
There must be no GPS alarms (if the modulator is in the test mode, the
GPS signal presence is ignored).
There must be no Up-converter alarms.
There must be no Reflected Power alarms.
5.3.1.2
Standby Mode
In this mode the repeater is off the air and affirms that the HPA is off while all other
components are operating normally. The up-converter output is muted, ALC is off, and
the HPA is switched off by disabling the HPA power supply.