Paradise Datacom P300 Series Installation & Operating Handbook page 73

The Scrambler selection is made from
Turns off all scrambling, and whilst this may be used for testing or carrier line
up, it is not normally used over satellite.
Selects the appropriate scrambler based on the current configuration, and
enables it (see table below).
The rationale behind this
Intelsats example of using Reed-Solomon with IBS or IDR, we have simply
used the first synchronous scrambler in the transmit chain even when two or
more are available. Also any synchronous scrambler is used in preference to
the V.35 self synchronising scrambler, as this will multiply received errors
degrading performance.
This allows non standard scrambler operation to match the configuration of
other non standard equipment which leads onto the following menus:
1=IBS (Off) 2=RS (N/A) 3=V.35 (On) 4=Turbo (N/A)
Change, Tx/Rx, Mod/Demod, Scrambler-Custom Menu
Pressing , , , or toggles each available scrambler between On and Off. Scramblers which are not
available are shown as N/A (Not Available) as they are out of circuit (eg Reed-Solomon scrambler when
RS is ). This screen specifically allows you to enable more than one scrambler, in order that you
might match the (mis)configuration of other equipment which allows the operator to accidentally switch
multiple scramblers on. When the V.35 style scrambler is enabled a subsequent menu is displayed.
1=CCITT 2=INTELSAT V.35 (Normal) 3=FDC 4=Linkabit
Change, Tx/Rx, Mod/Demod, Scrambler-Custom V.35 Menu
This screen then allows selection between CCITT V.35, INTELSAT V.35, FDC (Fairchild), and Linkabit
types. These are all different interpretations of the poorly defined V.35 scrambler specified by the CCITT.
Unless you are trying to inter-operate with another manufacturers equipment known to have an incorrect
scrambler, select INTELSAT mode as this is the most common.
Refer also to section 8.9 on page 154 which describes in more detail the different scramblers, and
interworking between manufacturers.
P300H P300 Series Modem Installation and Operating Handbook
,
Service type:
Closed Net (No ESC),
Closed Net + ESC (<32kbps),
IDR (& Custom IDR)
Custom IBS without TS32 MF
IBS/SMS,
Closed Net + ESC (>=32kbps),
Custom IBS with TS32 MF
Toggle Scramblers:
V.35 Style Scrambler [?]
, and .
No Reed-Solomon
FEC:
Non Turbo Turbo
V.35 Scr Turbo Scr
IBS/SMS synchronous scrambler
option is deceptively simple: Following
Reed-Solomon Active
Non Turbo Turbo
RS Scr RS Scr
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