Cisco GS7000 Installation And Operation Manual page 46

Chapter 2 Theory of Operation
Note: The transponder core module can be seen through the Heart
Beat/Receive/Error indicator cutout in the cover.
Local Control Module Description
The local control module locally monitors the following node voltages and signals:

Receiver optical input level

Transmitter optical output level

AC power presence and peak voltage (for split AC powering cases, AC
power from both sides of node housing is monitored)

DC voltages from both primary and redundant power supplies
The local control module communicates serially with the RF amplifier module to
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