Comtech EF Data CDM-740 - Manual (Page 59)

CDM-740 Advanced Satellite Modem Revision 0
Front Panel Operation MN-CDM740
5–7
When the Tx Monitor Port is turned On, an L-Band copy of the Tx carrier is provided. Note the
following:
• Monitor 70/140: Frequency = 900 MHz + programmed 70/140 MHz value;
• Monitor L-Band: Frequency = the programmed L-Band value;
• The monitor output mutes when Tx Carrier=Off.
5.4.1.2 (CONFIG:) Tx Æ Freq (Frequency)
Tx-IF Frequency: 0050.0000 MHz
( ◄► E)
To edit the Tx Frequency, select each digit of the frequency to be edited using the ◄ ► arrow keys,
then edit the value of that digit using the
▲ ▼ arrow keys. Press ENTER when done.
The available frequency ranges are 0050.0000 to 0180.0000 (50-180) MHz, and 0950.0000 to
2150.0000 (950-2150) MHz (L-Band). The resolution is 100Hz.
5.4.1.3 (CONFIG:) Tx Æ Power
Output Power Level: –10.0 dBm
( ◄► E)
To configure the Tx Output Power Level, select each digit to be edited using the ◄ ► arrow keys,
then edit the value of that digit using the
▲ ▼ arrow keys. Press ENTER when done.
For Tx frequencies of 50-180 MHz, the permitted level range is –5 to –25 dBm.
For Tx frequencies of 950-2150 MHz (L-Band), the permitted level range is –5 to –40 dBm.
5.4.1.4 (CONFIG:) Tx Æ FEC
Tx FEC Type: TPC (FPC)
This is a ‘status only’ message. The CDM-740 features TPC (Turbo Product Codec) as its sole
available Tx FEC type.
5.4.1.5 (CONFIG:) Tx Æ Mod (Modulation)
Mod Type=16QAM (QPSK,8QAM,16QAM)
FEC Rate=7/8 (3/4,7/8) ( ◄► vE)
On the top line, use the ◄ ► arrow keys to select (Tx) Mod(ulation) Type, then set the Mod Type
as QPSK, 8QAM, or 16QAM using the
▲ ▼ arrow keys. Next, using the ◄ ► arrow keys to
navigate to (Tx) FEC Rate on the bottom line, then set the Tx FEC Rate to either 3/4 or 7/8 using
the
▲ ▼ arrow keys. Press ENTER when done.