Command | Description | Parameters / Response Values |
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LO Freq | Sets the frequency to match your LNB downconverter local | 2000 to 15000MHz |
| oscillator frequency. |
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| Note: The IF frequency is the absolute value of the difference |
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| between the RF frequency and the LO frequency. The |
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| demodulator has a valid IF frequency in the range of 2150 MHz |
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| and 950 MHz. Entering values for RF or LO that equal an out of |
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| range IF frequency value will result in an IF value that is either |
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| the maximum or the minimum IF frequency. |
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Code Rate | Sets the Viterbi code rate | ■ QPSK: 1/2, 2/3, 3/4, 5/6, or 7/8 |
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| ■ 8PSK: 2/3, 5/6, 8/9 |
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| ■ 16QAM: 3/4, 7/8 |
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Sym Rate | Sets the demodulator to the frequency of the incoming RF signal. | 37500000 sps and 1000000 Sps |
| Note: If an | To convert symbol rate to data rate, use the |
| accept the new value and will revert to the previous value | following equation: |
| entered. | Symbol rate x 2 x (188/204) x FEC code rate |
| Since the data rate is proportional to the symbol rate, entering a |
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| data rate value might fail if the corresponding symbol rate is out |
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| of range. |
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| Converting a symbol rate to data rate and vice versa may be |
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| subject to a small rounding error. The error is less than |
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| 0.00001%. It is advisable to use the symbol rate representation |
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| when entering parameters if a conversion error cannot be |
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| tolerated. |
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| In cases where the demodulator is not locking on the carrier, it is |
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| necessary to add an offset to the symbol rate. This compensates |
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| for the symbol rate drift. The range of the offset is between |
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| 0.0002% and 0.0006%; in general a value of 0.0004% proves |
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| successful to lock on the carrier in these cases. |
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Data Rate | Sets the data rate of the transport data stream | 2 to 48Mbps |
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| To convert data rate to symbol rate, use the |
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| following equation: |
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| Data rate x 1/2 x (204/188) x 1/FEC code rate |
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LNB Power | Sets the voltage of the LNB | Off, 13 V, 18 V |
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Acq Range | Defines the size of the frequency range over which the | 0 to 7500000 Hz |
| demodulator will search for the carrier. |
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Details>Input>Config>Filter: allows you set the PCR filter |
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PCR Filter | Sets the PCR (program clock reference) filter for normal | ■ Normal: set for normal operations |
| operations or operations over an ATM network. | ■ ATM: set for operations over an ATM network |
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Details>Input>Status>RF: allows you to query the receive signal Eb/N0 level, the carrier offset, and the current lock status of the demodulator, decoder, and transport stream; this menu only applies to the currently active RF input.
Eb/N0 | Displays the value in dB; value is ± 2 dB | |
| Note: Eb/N0 is only available when | Eb/No values above 16 dB are not significant. |
| Details>Input>Config>Select>Input is set to RF. |
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Offset | Frequency in MHz | |
| The Offset measures the difference, in MHz, between the actual |
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| carrier frequency received by the TDR6 and the carrier |
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| frequency the TDR6 calculates by subtracting the LO parameter |
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| from the RF parameter. For optimum performance, the Offset |
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| parameter should be as close to zero as possible. |
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| For more information regarding the offset, refer to the chapters |
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| on configuration and troubleshooting. Also refer to the appendix |
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| on the QPSK demodulator. |
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| Note: Offset is only available when |
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| Details>Input>Config>Select>Input is set to RF. |
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Demod | Locked, Unlocked | |
| Note: Demod is only available when |
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| Details>Input>Config>Select>Input is set to RF. |
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Decoder | Locked, Unlocked | |
| Note: Decoder is only available when |
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| Details>Input>Config>Select>Input is set to RF. |
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Transport | Locked, Unlocked | |
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Rate | value in bps | |
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22 |
| Front Panel |