
P300H
P300 Modem Installation and Operating Handbook
Page 113
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.
FRM (L)
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
RS (L)
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
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)
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.