Interface Configuration and Interpretation

Configurations Allows you to select from a range of preset L-Band configurations.

The configurations are made available by the MTM400 configuration file (see MTM400 Configuration Files, page 3-85.).

You can activate an L-Band configuration by highlighting the name in the Configurations field; the field below will display the message ‘Updating values’ until the settings are recalled.

Local Oscillator Frequency (GHz)

The Local Oscillator (LO) frequency of the Low Noise Block (LNB) is dependent on the Transponder frequency and must be such that the difference falls within the input range of the receiver. Typically, these values are 10.6 GHz (Hi-Band) and

9.75GHz (Lo-Band) when converting from KU band. The values are 5.7 GHz (Hi-Band) and 5.15 GHz (Lo-Band respectively when converting from C-Band. This information should be confirmed for the specific type of LNBs used.

Enter the required value and select Set.

Transponder Frequency (GHz)

The IF frequency that is used to initialize the L-Band Interface card is calculated as follows:

Transponder_Frequency – LO_Frequency.

If you want to specify the IF frequency rather than the individual LO and Transponder frequencies, set the Local Oscillator Frequency to a value of 0 (zero) and specify the required IF frequency under this parameter. If the IF frequency is specified, it must be in the range 0.950 GHz to 2.150 GHz; the tuning increment is 125 kHz.

Enter the required value and select Set.

Polarisation (Volts)

This parameter selects the polarization by applying 13 V (vertical) or 18 V (horizontal) to the LNB (Low Noise Block). A value of 0 can be used if no voltage is to be applied from this card; for example, if the polarization voltage is being supplied from an external source.

Viterbi Rate Select the code rate from the drop-down list: 1/2; 2/3; 3/4; 5/6; 6/7; 7/8. Note that it may be overwritten if the Viterbi Rate Auto selection is enabled.

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MTM400 MPEG Transport Stream Monitor User Manual