Receiver Block Diagram - Cisco Prisma II Installation Manual

Chapter 1 Module Introduction

Receiver Block Diagram

Referring to the block diagram above (or below). The top OPM accepts two optical
inputs. The optical signals are converted to digital, unscrambled and converted back
to RF by DACs 1 and 3. These are signals are then routed to the top RF output (A)
through an RF switch network.
Similarly, the bottom OPM accepts two more optical inputs and uses DACs 2 and 4
to convert those signals back to RF. The RF switch network allows this combined
signal to be routed to the top RF connector (A) or the bottom RF connector (B).
The switching network on the right side of the block diagram also shows the test
point. The test point is fed by a 3 position switch which can pick off output A, output
B or neither.
There are four Enable controls (Enable1 – Enable4) that allow one to mute/unmute
the individual receiver inputs. These controls actually turn off the DACs.
There are four controls that, in combination with the Rx Mode setting, control the RF
signal routing through the switch network. In the 2.5G mode, these essentially act
like additional mute controls, but in the 5G mode, they allow control over the two
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