Paradise Datacom P300 Series Installation & Operating Handbook page 123

Options displayed on the second screen include all of the above, plus:
D/I (L)
FRM (L)
RS (L)
From the terrestrial port towards the IF ports the loopbacks in the following order test more and more
circuitry: Interface, Drop/Insert, Framer, Reed-Solomon, FEC, IF.
REMOTE (R)
P300H P300 Series Modem Installation and Operating Handbook
The data is looped back after the Drop mux, through the Doppler buffer, back into
the Insert mux providing a local loop only. The Tx data continues to be transmitted
and the Rx data from the satellite is ignored. If Drop/Insert baseband processing
is not active, this loops the data at the output of the baseband block (ie it works
even if Drop/Insert is not active). ESC & Aux channel data is NOT looped.
The data is looped after the Framer back into the Deframer providing a local loop
only. The Tx data continues to be transmitted and the Rx data from the satellite
is ignored. ESC & Aux channel data (which is present in the data stream at the
Framer output) is also looped
The data is looped after the Reed-Solomon Encoder / interleaver back into the
RS Deinterleaver / decoder providing a local loop only. The Tx data continues to
be transmitted and the Rx data from the satellite is ignored. ESC & Aux channel
data (which is present in the data stream at the RS codec) is also looped
This provides a loop of the Rx data after the deframer back into the framer. Tx
input data is ignored, Rx traffic continues as normal. Incoming ESC & Aux channel
data is not looped back to the remote site.
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