3-18
Operation
4038501 Rev C
Functions of the AGC Module
Standby
If no function is required, the AGC module is automatically set to Standby mode to
reduce power consumption. The standby mode is running in a cycle of 2 minutes
between monitoring and sleeping. In monitoring status, the AGC module detects the
levels of 4 pilots and the selected frequencies and sends the information back to the
handheld or the ROSA Element Management system. In sleeping status, the
microprocessor in AGC module continues communicating with the amplifier.
Auto Alignment
The auto alignment function adjusts input attenuator and equalizer to get the
desired output level and tilt, according to the pilot levels set up as per page 3-17.
When the auto alignment function is selected, if the differences between the detected
pilot levels and the set pilot levels are less then ±1 dB, the auto alignment function is
completed, and the AGC module goes back to Standby mode. Otherwise, the auto
alignment continues until one of the following occurs:
The differences are less than ±1 dB;
Auto alignment is timed out. After 2 minutes of auto alignment, a time-out
alarm is activated, either shown on the LED indicators, the handheld, or in the
ROSA Element Management system. See page 3-16 for the descriptions of LED
indicators. Meanwhile, the current input attenuator and equalizer values
remain, and the AGC module goes into Standby mode.
No input attenuator/equalizer can be adjusted. In this case, an alarm is
activated, either shown on the LED indicators, the handheld, or in the ROSA
Element Management system. See page 3-16 for the descriptions of LED
indicators. Meanwhile, the current input equalizer value remains, but the input
attenuator value is set to its maximum, and the AGC module goes into Standby
mode.
In the auto alignment function, when all the high or low pilots and their backup
pilots drop out, the current input equalizer value remains, while the input attenuator
value is set to its maximum, and the AGC module goes into Standby mode.
The user cannot switch the AGC module to other functions, or change the values of
attenuator or equalizer, until the auto alignment is completed. At this time, both
attenuator and equalizer values are updated in the handheld or ROSA Element
Management system. And if the AGC module is pulled out of the amplifier during
the auto alignment, the input attenuator and equalizer values are saved.
Note:
Special attention is required when using the auto-alignment function. This
function is used for adjusting the input attenuator and equalizer only. Before
running the auto-alignment function to automatically set the input attenuator and
equalizer, make sure to manually set the interstage attenuator and equalizer to a
desired value first.
Continued on next page
