Motorola SG 2000 operation manual Digital Return Path, Digital return transmitters

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O v e r v i e w

Digital Return Path

The digital return transmitter series (DS-SG2-DRT*) converts a broadband analog RF return-path signal into digital optical signals with 10-bit resolution.

The transmitters used for digital return applications are divided into two families: DS-SG2-DRT/A and DS-SG2-DRT-2X/A.

Seven digital return transmitters per family are available to meet the needs of most digital return applications.

Table 2-2 identifies the fourteen optical digital return transmitters:

Table 2-2

Digital return transmitters

DS-SG2-DRT/A

DS-SG2-DRT/A-1310 FP DS-SG2-DRT/A-1310 DFB DS-SG2-DRT/A-1470 DFB DS-SG2-DRT/A-1490 DFB DS-SG2-DRT/A-1550 DFB DS-SG2-DRT/A-1510c (2) DFB DS-SG2-DRT/A-1530c DFB DS-SG2-DRT/A-1550c DFB DS-SG2-DRT/A-1570c DFB DS-SG2-DRT/A-1590 DFB DS-SG2-DRT/A-1610 DFB

DS-SG2-DRT-2X/A

DS-SG2-DRT-2X (1)/A-1310 FP DS-SG2-DRT-2X/A-1310 DFB DS-SG2-DRT-2X/A-1470 DFB DS-SG2-DRT-2X/A-1490 DFB DS-SG2-DRT-2X/A-1550 DFB DS-SG2-DRT-2X/A-1510c DFB DS-SG2-DRT-2X/A-1530c DFB DS-SG2-DRT-2X/A-1550c DFB DS-SG2-DRT-2X/A-1570c DFB DS-SG2-DRT-2X/A-1590 DFB DS-SG2-DRT-2X/A-1610 DFB

(1)2X in the model number denotes time division multiplexing (TDM)

(2)c in the model number denotes coarse wave division multiplexing (CWDM)

To prepare for an anticipated increase in return traffic, provisioning for CWDM is built into the transmitters. The CWDM option consists of lasers at predefined wavelengths. This option is available to support multiplexing in the optical domain, using eight-wavelength wave division multiplexing (WDM) in the DS-SG2-DRT/A-15XX DFB and DS-SG2-DRT-2X/A-15XX DFB windows.

DS-SG2-DRT/A

The DS-SG2-DRT/A digitizes a single analog 5-42 MHz return path signal to produce a 1.6 Gbps data stream. This data stream is then routed to a digital laser for transmission to a corresponding digital return receiver. The node can be configured with one or two DS-SG2-DRT/A transmitters, with dual transmitters providing redundancy. In conjunction with these transmitters, the node must also be configured with the SG2 Return Path Module/Combined (SG2-RPM/C). The return signals from all four ports are combined and fed to the optical transmitters.

SG 2000 Installation and O peration Manual

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Contents A R L I N E Special Symbols that Might Appear on the Equipment Contents E r a t i o n InstallationTorque Specifications Abbreviations and Acronyms Specification sSG2-LR Tables N t e n t s SG 2000 closed SectionSG 2000 open Features includeRelated Documentation Using this ManualIf You Need Help Document ConventionsBold type Calling for Repairs SG 2000 housing dimensions front and side view HousingMounting Holes Port locations Port LocationsGaskets Housing gasketsSG2-PS2 power supply Power SupplyNetwork Monitoring ConfigurationTo suit system requirements the RF chassis cover. notation Forward Path Signal flow diagramE r v i e w SG2-LR Receiver SG2-LR receiver functional diagramAnalog Return Transmitters Analog Return PathModel Description Analog return transmittersJXP SG2 transmitter block diagramDigital return transmitters Digital Return PathDS-SG2-DRT-2X/A Options and accessories Options and AccessoriesLevel Control Model Description FunctionSG2-PS2 SG2-SBSG2 SG2-FEOptical input versus 750 MHz gain Gain SelectionOptical input versus 870 MHz gain 10 illustrates the gain option selection chart for 870 MHzRelative level dB versus 750 MHz slope 77 channels Tilt SelectionRelative level dB versus 870 MHz slope 94 channels SG2 870 MHz Slope Chart Analog Channels, 220 MHz DigitalRelative level dB versus 870 MHz slope 110 channels SG2 870 MHz Slope Chart Analog Channels, 120 MHz DigitalN c h S e t u p G u r e 3 2 0 0 0 R F c h a s s i s W e r i n g t h e N o d e Fuse Functi o n Rati ng Ype W e r S u p p l y S e t t i n g s Illustrates the location of the LO-HIjumper Single Power Supply or Commonly Po wered Redundant Supplies I c k C h e c k s F u n c t i o n a l T e s t i n g N u a l G a i n C o n t r o l Analog Retu rn Path R w a r d P a t h P a d d i n g B l e 3 2 0 0 0 p a d c h a r t s t a n d a r d g a i n B l e 3 2 0 0 0 p a d c h a r t h i g h g a i n G u r e 3 N k P e r f o r m a n c e G u r e 3 1 N c h S e t u p Install i n g t h e D S S G 2 D R R B B o a r d O p t i o n G u r e 3 1 S G 2 D R R B b o a r d Install e d G u r e 3 1 C a t i o n o f J X P s o n E p a c k Digital Transmitter Install i n g t h e S t a t u s M o n i t o r O p t i o n 2 0 0 0 a c t i v a t i o n W o r k s h e e t DC powering Splicing Fiber Service cable connection and compression fittingInstallation Mounting bracket-front view Strand Wire MountingMounting bracket-rear and side views Fiber Cables Coaxial CablesCenter conductor length Housing lid and fiber spool tray Fiber spool tray Installation Single Receiver Mode Forward Path RF ConfigurationBroadband/Narrowcast Mode Redundant Receiver ModeRedundant receiver Broadband/narrowcastOverride AB Override FunctionalityStatus monitor/MCB operation Status Monitor/Manual Control OperationRedundant return Analog Return Path RF ConfigurationSplit return RF chassis and location of the SG2-RPM/C or SG2-RPM/S board DS-SG2-DRT/A redundant return Digital Return Path RF ConfigurationDS-SG2-DRT-2X/A redundant return DS-SG2-DRT-2X/A split returnSG 2000 Optical Modules Installing SG 2000 Optical ModulesRemoving SG 2000 Optical Modules SG2 LR Optical Receiver Cleaning the Optical ConnectorFeature Description 0.3 Test-point voltage versus optical powerWavelength selection jumper Wavelength Selection JumperSG2-IFPT features FeatureDescriptionSG2 Ifpt Optical Transmitter SG2-FPT features Transmitter enableSG2 FPT Optical Transmitter SG2 Dfbt Optical Transmitter SG2-DFBT featuresSingle red LED that lights if the hybrid current is outside SG2 DFBT/3 Optical Transmitter SG2-DFBT/3 featuresSG2 Eifpt Optical Transmitter SG2-EIFPT featuresDS-SG2-DRT/A DS SG2 DRT/A Digital Return TransmitterDS-SG2-DRT/A features FeatureDS-SG2-DRT-2X/A DS SG2 DRT 2X/A Digital Return TransmitterDS-SG2-DRT-2X/A features DS-SG2-DRT-2X/A installed in SG DS-SG2-DRT-2X/A cable connectorSG2-PS power supply SG2-PS Power SupplyDS-SG2-DRT-2X/A second RF input cable connection Parameter Description Status MonitoringDescription Function Manual Control BoardDB test point Alarm test pointPotentiometers ICS1 Through ICS4State Description Ingress ControlOff Table A-1 SG 2000 optical characteristics Parameter SpecificationTable A-2 Station RF characteristics Appendix aParameterSpeci fic ation Table A-6 SG2-FPT RF specifications Table A-5 SG2-IFPT RF specificationsParameter Table A-8 SG2-DFBT/3 RF specifications Table A-7 SG2-DFBT RF specificationsTable A-10 SG2-DRT/A RF specifications Table A-9 SG2-EIFPT RF specificationsTable A-11 SG2-DRT-2X/A RF specifications Minimum Optical Model Output Power DBmOption Watts ac Amps Power @90V @60V @52V @44V Table A-14 SG2-75 performance, with 77 channels Channels Link Launch SystemTable A-15 SG2-87 performance, with 94 channels Table A-16 SG2-87 performance, with 110 channelsTorque Fastener Screw Size Wrench Size In-lbs Ft-lbs DBm DBcDBmV MHzSnap connector Return for service authorizationNational Television Standards Committee Optical modulation indexMgbi