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5 config: rx ( descrambler, 6 config: rx ( ebno – Comtech EF Data CDM-600/600L User Manual

Page 94

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CDM-600/600L Open Network Satellite Modem

Revision 3

Front Panel Operation

MN/CDM600L.IOM

5–18

When Insert Framing or the G.703 interface type is used, the [

][] arrow keys will scroll

through the available data rates. If in Drop Mode and the data rate is edited to 1920 kbps, a
comment is shown to indicate that E1 fixed channel mode will be implemented.

When G.703 is used and the Modem is Hardware Revision 2.0 or higher, three auxiliary rates will
also be available (512, 1024 and 2048 kbps) indicated by the word AUX appearing to the right of
the decimal place (e.g.,

00512.AUX kbps

).

Refer to Sect. 3.3.4.2 J10A IDI, J11A DDO Connectors for additional information about how to
connect the cables for the AUX data rates.

The bottom line permits the user to select the data inversion feature (added for compatibility with
certain older equipment). Set DATA INVERT to ON or OFF using the [

][] arrow keys, then

press [ENT] when done.

5.4.4.5

CONFIG: RX

Æ DESCRAMBLER

RX DESCRAMBLER = NORMAL (NORMAL,OFF)
DECODER DESCRAMBLER

Select Normal or Off using the [

][] arrow keys, then press [ENT]

The choice of descrambler used for Normal is selected automatically, and depends on the exact
operating mode. For example:

• If no framing is being used, the ITU V.35 descrambler (Intelsat variant) will be used.
• If IBS framing is selected, the IESS-309 descrambler will be used, etc.

If LDPC encoding is selected, the standard ITU V.35 descrambler will be used.

If Turbo encoding is selected, a second scrambler, IESS-315 V.35, is available instead of the TPC
descrambler:

RX DESCRAMBLER = IESS (NORMAL, IESS, OFF)
IESS-315 V.35 DESCRAMBLER

5.4.4.6

CONFIG: RX

Æ EbNo

RECEIVE EbNo ALARM POINT = 02.0 dB

(

34v)

Edit the Rx EbNo Alarm Point by selecting the digit to be edited using the [

][] arrow keys,

then edit the value of that digit using the [

][] arrow keys. Press [ENT] when done.

The permitted range is from 00.1 to 16.0 dB.

Note: If the Rx Eb/No falls below the permitted range value and the fault is NOT masked, a
receive traffic fault will be generated.