Kathrein MSK 33, 9986492 Constellation diagram DVB-T optional, Measurement of bit error rate BER

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DVB-T

Constellation diagram DVB-T (optional)

For the terrestrial digital transmission of television signals (DVB-T), the modulation type COFDM (Orthogonal Frequency Division Multiplex) is used.

In 2k mode, 1705 carries and in 8k mode 6817 carriers either QPSK-, QAM16- or QAM64 are modulated.

DVB-T signals are transmitted in the so-called hierarchy modulation. Two MPEG transport streams of difference priority are simultaneously transmitted.

The demodulated QPSK signals are decoded in the MPEG decoder and their con- stellations are represented on the screen of the MSK 33.

THE MSK33 can automatically represent the constellations of all possible modula- tion types and display the respective values.

param. on►

By pressing this softkey, you receive all data of the DVB-T signal (see left).

Measurement of bit error rate (BER)

Since it deals with the transmission of binary data for DVB-T, the bit error rate can be observed as measurement for the occurring transmission error in the data stream. The BER measurement is carried out before and behind the viterbi decoder and displayed on the screen. The bit error rate is the ration of the number of the received defective bits divided by the entire number of receive bits. The low bit error rate, which the MSK 33 can measure, is

1.0e-8. If the measured value is below this value, the display of BER skipped to zero „0“ (no bit error available). The highest displayed BER is 1 e-2. Generally, it can be assumed, that the picture disturbance can occur for a BER of ca. ca. 2.2 e- 2 before viterbi.

Measurement of signal noise ration (SNR)

The conception of the MSK 33 allows the S/N ratio of the I- and Q- data stream to be displayed in addition to the C/N measurement on the digital carriers in the Const-menu. The measurement is carried out after the QPSK demodulation and can be called in as an indicator for the noise on the I/Q signals. Differences in the result to the C/N measurement in the spectrum menu can be caused by the com- plex interfering influences of the digital signal or by differences in the input level. The SNR value is displayed on the upper edge of the TFT screen.

The best value, which the MSK 33 can measure, is 32 dB.

Carrier offset

The carrier offset display represents the difference between set receiving fre- quency on the MSK 33 and the transmission frequency of the digital signal in MHZ. With the cursor buttons, ◄►, you can switch to the next channel.

Carrier mode

Displays how many carries of the DVB-T signal are modulated. It is modulated be- tween the 2k mode (1705 carriers) and the 8k mode (6817 carriers).

Modulation

Displays the modulation type, with which the DVB-T carriers are modulated. The modulation types QPSK, QAM16 and QAM64 are possible.

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Contents Sat/TV/FM Test Receiver MSK Page Preface Contents Checking the LNB supply voltage of a satellite receiver Selecting the colour standards PAL, Secam and Ntsc Mpeg transport stream interface TS-Parallel, Lvds optional Measuring an audio signal via the AV socket Scart Measurement of analogue signals in Sat operation 100 107 113General safety information Explanation of symbolsImportant Notes Validity of this manualSafety Instructions ConnectionsProper use Mechanical loadbearing capacityFunctions FunctionsFunctions overview FunctionReturn path LP DVB-S DVB-S/C/TDisplays, Operating Elements and Connections Front panelMains connection Mains switch DC socket Option / XLR-socket Rear panelHeadphone connection TS parallel Option 10 AUXObserving angle of the on screen display Side view MSKFrequently recurring softkeys Operating ConceptScreen General information for operation Menu selectionMain menu Accu CAP % I=0.00 aPlace of installation of the MSK Mains voltage / mains switchOn/Off switch Safety fuseDC socket option Accumulator and Battery OperationAccumulator operation Connections Maximal input level Measurement PossibilitiesLevel measurement Sat Operation Sat menuEntering the transponder frequency Setting of the LNB voltage supplySelecting the LO frequency Switch-over of Analog digit. Dvbs Bargraph Level range Comment DisplayIII Calling up menu LNB-CONTROLKHz control signal LNB control menuLNB supply voltage LNB current drawDiSEqC Checking the LNB supply voltage of a satellite receiverCalling up the DiSEqC/V SEC menu DiSEqC menu Submenu for entering DiSEqC commands TX display fieldDisplay field a Display field BData burst Tone burst Example Entering and transmitting a DiSEqC commandSimple DiSEqC UFOmicro DiSEqC menu General informationDisplay fields RX 0 E2 10Tx+rx Command 1390Operating the menus ModusSat Operation Entering the hex numbers Sending a V-SEC command TXSEC menu Level-dependent acoustic signal Initial ANALOG-menuCalling up the sound subcarrier MenuSecond Anlaog menu Video polarityAudio carrier setting Setting of the de-emphasisSat subcarrier menu Audio carrier frequencyAudio carrier tables for the satellite reception Audio carrier table for reception type27.500 Digital MeasurementsSAT Digital menu Level measurement Digital Min./Max. levels TV Operation TV menuC10 210.25MHz A65.0dBµV Rf chanLNB U= 0.0 V I= 0 mA TV control menuTV-DiSEqC /VSEC menu Analogue menu Selecting the standardAudio carrier table for TV reception Selecting the audio carriersMeasuring the min./max. level Measuring the current levelSelecting the colour standards PAL, Secam and Ntsc Measuring audio carrier spacingTV Digital menu Selecting demodulation for DVB-C measurementMode 900 SR1ChBW 8MHz DVB-T optionalSelecting channel bandwidths Return Path if Menu Return path if menuAnalog menu Audio carrier table for if receptionMeasurement of the current level Measurement of the min./max. levelMeasurement of the audio carrier spacing If RP Digital Menu QAM64 modeEntering symbol rate Radio Analog menu Radio OperationRadio menu FM Measure ALL Measuring the min/max levelAV Menu Decoder operationDecoder operation baseband Video input Video outputMpeg transport stream interface TS-Parallel, Lvds optional Breaking voltageRGB operation 3sat KiKa Phoenix Mpeg Decoder Menu OptionalPAT 08 Offset 0.0 dB Setting MenuUnit dBmV Screen setup Screen MenuSetting the date Setting the time Click buttonSystem Menu Calls up the SYS TEM menuSaving and calling up unit settings Saving the unit settingsCalling up saved settings Copy MenuPrinting out all measurements in TV mode Printing out all measurements in Sat modeMode Menu SpectrText Menu Enlarging the videotextHolding the videotext Original videotext sizeHorizontal zoom Reducing the video signal Horizontal zoom -Enlarging the video signalScope Menu Video scope menuSelecting the video line Measurement of the amplitude of the video signalMeasurement of video signals via the AV socket Scart Pos Audio ScopeTime Position and triggering of the DiSEqC signal DiSEqC ScopeSaving function Shot ContSpectral Menu Marker Span Large ¡ mark ßlevelAna MaxMarker Ana Marker DigZoom marker Max off Measurement of digital signals in Sat operationCross-polarisation measurement on signals in SAT operation Constellation diagram for Qpsk DVB-S Measurement of the bit error rate BERConst Menu Colour representation of I/Q value pairsFrontend locked Measurement of signal noise ratio SNRCarrier offset Selecting the symbol rate symbol-clock Inverting /not inverting a constellation diagram27.500 SR Selecting the code rateExamples for Qpsk constellation diagrams Constellation diagram for QAM DVB-C Measurement of modulation error rate MERInverting /not inverting constellation diagram ZoomExamples for QAM constellation diagram Const Menu Constellation diagram DVB-T optional Measurement of bit error rate BERMeasurement of signal noise ration SNR Carrier modeHierarchy Code rate Guard Invers Frontend locked Channel display Impulse response representation Echo representation optional Broadband Cable Analysis Measuring System MSK Measuring principleTrack MVG10 Upstream measurement Downstream measurementMSK33 MVG10 RGB MSK33Cable system With return path capable amplifiers Auto Measure Display of the check pointConnection cable for modem / RS InterfacesModem / RS 232 interface Setting baud rate Setting local echoSetting hardware handshake Modem/RS232 menuCode Password TTY modeAnsi mode Log-in procedureExample for logging-in in Ansi mode Requesting helpInterfaces List of the command abbreviations Loading and saving predefined settings STUSTU RET LDUMaintenance, Storage and Customer Service Ribbon exchange Printer paper-exchanging the ribbonBefore opening the unit, disconnect the supply voltage Overview of DiSEqC commands Command overview framing byteCommand overview address byte Technical AppendixCommand overview command byte Reset Reset DiSEqC minicontrollerDiSEqC commands for Kathrein matrices Command overview data byteCommand for Kathrein matrix 9xx-series Command for Kathrein matrix EXRChannel tables Channel and frequency table standard B/G frequency in MHzVHF-CCIR UHF-CCIR USB/OSB ESBChannel and frequency table standard Lfrequency in MHz VHF UHFChannel and frequency table standard D/K frequency in MHz VIIViii XIIChannel and frequency table standard I frequency in MHz Channel and frequency table standard M/N frequency in MHz Channel and frequency table standard M/Nfrequency in MHz Power supply Technical DataTechnical data MER SNRQpsk BER Assignment of the Scart socket AccessoriesScope of delivery Assignment of RS232 socket TXD RXD RTS CTS DSR GND DCD DTRAssignment of socket TS Parallel optional Unit variants Downloading New MSK33 Operating Software General notes114 115
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