System information

© 2006 Cisco Systems, Inc. All rights reserved. Cisco Confidential Presentation_ID Kirkpatrick 092509
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1310 TX Operation
 Transmitter gain is controlled through the selection of Manual or Automatic
Gain Control (AGC) mode operation.
 In Manual mode, an attenuator can be used to reduce RF power in an
overdrive condition or to compensate for variations in transmitter gain. Any
manual attenuator adjustments are reflected in the indicated RF drive
level. It may be desirable to make such adjustments to compensate for
power differences if the channel load differs from the specified value.
 In AGC mode, the microprocessor monitors the actual input composite
power and adjusts the attenuator to maintain constant RF drive level into
the laser diode.
Note: If Analog or QAM loading is to remain constant – not expanding
using AGC is OK however IF channel load differs the AGC will self
adjust accordingly resulting in RF level change at Node RX.