Paradise P300 Performance, Non standard equipment which leads onto the following menus

NORMAL Selects the appropriate scrambler based on the current configuration, and enables it (see table below).

FEC:

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

No Reed-Solomon		Reed-Solomon Active
Non Turbo	Turbo	Non Turbo	Turbo
V.35 Scr	Turbo Scr	RS Scr	RS Scr
IBS/SMS synchronous scrambler

	The rationale behind this “NORMAL” option is deceptively simple: Following
	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.
Other	This allows non standard scrambler operation to match the configuration of other
	non standard equipment which leads onto the following menus:
	Toggle Scramblers:
	1=IBS (Off) 2=RS (N/A) 3=V.35 (On) 4=Turbo (N/A)
	Change, Tx/Rx, Mod/Demod, Scrambler-Custom Menu

Pressing 1, 2, 3, or 4 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 Off). 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.

V.35 Style Scrambler [?]

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 152 which describes in more detail the different scramblers, and interworking between manufacturers.

The operator is warned of unusual scrambler settings when SETUP-CHECKis requested.

P300H P300 Series Modem Installation and Operating Handbook Page 70