CDM-Qx Satellite Modem

Revision 5

Front Panel Operation

MN/CDMQx.IOM

(Config„Rx„Freq) – RX FREQUENCY

Rx IF Freq: 1156.3456 MHz (◄ ►, ▲ ▼,ENT)

Edit the receive frequency. This is accomplished by selecting the digit to be edited, using the WXarrow keys. The value of the digit is then changed using the STarrow keys. The user should then press ENT. The range of frequencies depends upon the plug-in module. The above examples shows the L-Band version of CDM-Qx.

If (using the ODU, LNB menus) the user has selected an LNB LO frequency (other than zero) and defined whether the mix is high side or low side, the display will be modified as shown below, to include the calculated Receive RF frequency of the modem/BUC combination:

Rx IF Freq:1156.3456 MHz

RF=12156.3456 (◄ ► ▲ ▼ ENT)

As the Rx IF frequency is edited the RF frequency will automatically be updated

(Config„Rx„Acq) – DEMOD ACQUISITION RANGE

Demod Acquisition Range:

+/- 32 kHz

(▲ ▼ ENT)

Edit the acquisition search range of the demodulator (the value entered here determines the amount of frequency uncertainty the demodulator will search over in order to find and lock to an incoming carrier). Editing the value is accomplished by selecting the digit to be edited, , using the W Xarrow keys. The value of the digit is then changed using the STarrow keys. The user should then press ENT.

The range varies from ± 1 kHz to ± 32 kHz for 70/140 IF, ± 1 kHz to ±(symbol rate/2) up to ±200 kHz for L-Band. For symbol rates < 64 ksps, it will be ± (symbol rate/2)

The value entered here determines the amount of frequency uncertainty the demodulator will search over in order to find and lock to an incoming carrier.

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Mocomtech CDM-QX operation manual Config„Rx„Freq RX Frequency, Config„Rx„Acq Demod Acquisition Range