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Carrier mode normal-modulated, Modem reference internal – Comtech EF Data SNM-1001L User Manual

Page 77

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SNM-1001L Satellite Modem

Revision 1

Front Panel Operation

MN/SNM1001L.IOM

4–13

FUNCTION SELECT: CONFIGURATION: MODULATOR:
CARRIER MODE

CARRIER MODE

NORMAL-MODULATED


Programs the modem for alternate carrier modes. All modes, except Normal-Modulated are Test
Modes
. Four modes of operation are available:

NORMAL-MODULATED

This mode is normally selected.

CENTER-CW

Generates a CW-carrier at the current modulator frequency. This can be used to
measure the output frequency.

DUAL-CW

Generates a dual side-band suppressed carrier signal. Side-bands are at one-half of
the symbol rate from the carrier. This is used to check the channel balance and
carrier null.

OFFSET-CW

Generates a single, upper, side-band-suppressed carrier signal. The upper side-
band is at one-quarter of the symbol rate from the carrier. When inverted spectrum
is selected, this generates a single, lower, side-band-suppressed carrier.


Upon entry, the Center mode is displayed. To activate this test mode, press . Press [

↑]

or [

↓] to select the desired mode. To return to the Configuration menu, press [CLEAR].

FUNCTION SELECT: CONFIGURATION: MODULATOR:

MODEM

REFERENCE

MODEM REFERENCE

INTERNAL


Select either: Internal, EXT1 MHz, EXT5 MHz, EXT 10MHz, EXT 20MHz, or
Output 10 MHz.

IMPORTANT

Use only Internal or EXT 10 MHz with a Block Up Converter (BUC) or
Outdoor Unit (ODU).


Upon entry, the current status of the scrambler is displayed. Press [

↑] or [↓] to make the selection.

Press to execute the change.

Note: If any EXT REF is selected for the modem reference and is disconnected or not present at
CP3, an alarm is generated, and the modem switches to its Internal Clock.