JVC TDR6 installation and operation guide Diagnostic Commands

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Measure C/N to estimate Eb/N0 where

C is carrier power N is noise floor

Calculate the estimated Eb/N0

Refer to the equation for estimating Eb/N0 using a spectrum analyzer in a previous section of this appendix.

Transmit pure carrier to precisely locate the center frequency

If the demodulator is supplying the DC to the LNB, then the spectrum analyzer must monitor the L-band input using a T-junction. Insure that the spectrum analyzer input is protected using a DC-block. Since the spectrum analyzer has an input impedance of 50 ohms, this method will also

NOTE double-terminate the input signal (i.e. lower it by 3 dB).

The demodulator will acquire only if the input carrier frequency is equal to [(RF – LO) ±2 MHz]. Once acquired, it is recommended that you optimize the RF parameter using the carrier offset status parameter. For the optimization procedure, refer to the chapter on configuring the TDR6.

Diagnostic Commands

This section describes commands you can use for troubleshooting the demodulator.

G4 – Use this command to display the demodulator IC registers.

Syntax – DMD.x G4 where x designates the demodulator that is the object of the command.

Register Values – The register values are all in hexadecimal. The two registers that are most useful for debug are Register 6 and Register 31.

Register 6 (Power Level) – This register should be almost equal to A0. This indicates that the AGC loop is locked and the signal level is optimum at the analog-to-digital converter inputs.

Register 31 (Status) – Only the three least significant bits are active.

Status[0] = 1 if the symbol clock is locked Status[1] = 1 if the carrier phase is locked Status[2] = 1 if the carrier frequency is locked

Note that the state of these three bits are reflected in the status LED’s.

G3 – Use this command to display the three decoder error count registers.

Syntax – DMD.x G3 where x designates the demodulator that is the object of the command.

Register Values – The register values are all in hexadecimal.

Reed-Solomon Corrected – This register displays the total number of byte errors corrected by the Reed-Solomon decoder. It is reset to zero upon reaching max count.

Any substantial channel noise will cause this register to be greater than zero.

Reed-Solomon Uncorrected – This register displays the total number of byte errors that were detected, but not corrected, by the Reed-Solomon decoder. It is reset to zero upon reaching max count. For normal operation this register must be zero.

Any non-corrected byte errors will result in some form of degradation in the decoder.

Demodulator Application Notes

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Contents TDR6 Electric Shock Hazard Contents Appendix G Demodulator Application Notes Chapter Configuring the TDR6Chapter Troubleshooting Appendix F Option Module OverviewImportant Information Using This GuidePreface Locating InformationRevision Issuing CommandsFront Panel Navigation DisplaysLCD Display ErrorsCartons and Packing Materials Miti SAAIMQ OVEUse Approved Attachments Only Viii 01-0870-401B 01/03 Overview Overview Overview 01-0870-401B 01/03 Ventilation Installing the TDR6AC Power Cords Power-up Sequence Connecting to a Power SourceBasic TDR6 SD Configuration with No Option Modules Installed TMAC-6125 Ports Connecting to a Remote UnitConnecting to a Network TDEC-6161 Ports Cabling the Analog Audio ConnectorsCabling the TDEM-6110 LNB Power01-0870-401B 01/03 TDR6 Front Panel Front PanelTDR6 DTV Receiver/Decoder Menu Structure LCD Text Formats LCD Display LCD SymbolsData a Menu Qpsk Key Character Displayed Correcting Mistakes Example QPSK, 8PSK, 16QAM Command Description Parameters / Response ValuesDVB DetailsInputConfigFilter allows you set the PCR filter BER Message No services availableNTSC, PAL, Auto PIDMPEG-2 Value, that does not begin with EID Important Considerations when entering Biss EkeyMAC ControlEIA-232 used to configure the remote portLocking the Front Panel Restoring a Default ConfigurationRestoring a User Configuration Saving a User ConfigurationUnlocking the Front Panel Setting the DateSetting the Time Performing a System ResetRemote Port Using a Remote UnitConfiguring Remote Software Parameters Ethernet Port Command TypesBaud 01-0870-401B 01/03 TDR6 HD/SD Back Panel with Remote Designators Informational Remote Commands Response Error Messages Explanation Action RequiredLang DelayAuto ChannelmodeBiss Sample RateSource MPEG-2, Atsc MPEG2 VOLDC Filter Biss ModeBiss Status DC AutoselLNB DclockDmlock EbnoTune FaultlogclearHdvd Delay Rolloff 35RCRO, 25RCROMC Config List MC Access CodeMC Access FP RO, RW MC Access UnlockMC Ethernet IP Address MC Default RestorePgca Authorization Pgca ModeInterface Pgca TimeoutData HandshakeVBI Format VD DelayVBI VBI ControlVD Submode VD Mode PAL, NTSC, AutoVD Setup VD PIDQuick Start Configuring the TDR6Configuration Selecting a Service Demodulator Configuration Detailed TDR6 ConfigurationSetting Local Date and Time TDR6 Detailed Configuration ProcedureConfiguring the L-Band Carrier Frequency Qpsk Parameter Front Panel Menu Remote Command01-0870-401B 01/03 Fault History TroubleshootingFault Reporting and Monitoring Current FaultsCommand Mnemonics Abbreviation Option Module Fault Descriptors are defined in the following table Viewing the Fault History Log Viewing Current FaultsMinimum E b /N 0 dB Input Status LED Not IlluminatedPerformance Problems FACTORY-CONFIGURABLE Features Technical SpecificationsStandard Features High-Definition Video Decoder Default ConfigurationsDemodulator a D Standard-Definition Video DecoderUser Data a B Remote ControlAudio Decoder a F Ethernet Front Panel Access01-0870-401B 01/03 Port Pinouts Fault Relay Port Pin SpecificationsNumber Synchronous Asynchronous Ethernet Port Pin Assignments Signal Signal DefinitionUser Data port Pin Specifications Standard RS232 TMAC-6125 Specifications Port SpecificationsTAUD-6100 Specifications TDEC-6100 SpecificationsTDEC-6161 Specifications LNB Port Specifications TDEM-6110 Specifications01-0870-401B 01/03 PAL Tiernan VBI Data TransmissionTiernan VBI Data Transmission Tiernan Proprietary Closed Captions Tiernan CC Tiernan CC Mode is for Ntsc Format OnlyDVB 422 Expanded Windows, 16-line and 32-line Lines Expanded Windows Field for an Encoded Picture Frame Tiernan Closed Captions Front Panel Commands Front Panel Commands for Encoder Configuration32LINES Remote Commands for Encoder ConfigurationVE TCC VE Vbipass01-0870-401B 01/03 Typical Option Module Option Module OverviewOption Module Overview Demodulator Tuner SAW Filter Demodulator Application NotesIndustry Standard LNB Frequencies Spacing Information RateTransponder Output Spectrum WidthEb/N0 Definition Minimum and Maximum Information RatesSpectrum Analyzer Estimating Eb/N0 Using a Spectrum AnalyzerDemodulator Low Eb/N0 Alarm Eb/N0 Estimation AlgorithmDiagnostic Commands Offset = Actual RF Programmed RF Table Top and Rack Mount Installation Instructions Rear Rack Mount Instructions Fuse Rear Rack Bracket Mounting Instructions01-0870-401B 01/03 Index Index