Motorola SG 2000 operation manual DS SG2 DRT 2X/A Digital Return Transmitter, DS-SG2-DRT-2X/A

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O p e r a t i o n

DS - SG2 - DRT - 2X/A Digital Return Transmitter

The DS-SG2-DRT-2X/A is an SG2 return transmitter that digitizes two independent analog

5 MHz-42 MHz return-path signals to produce two 1.25 Gbps data streams. These two data streams are then multiplexed to create a 2.5 Gbps data stream. This data stream is then routed to a digital laser for transmission to a corresponding digital return receiver.

The transmitter can be configured with a digital laser wavelength that is applicable to the required link length. An APC system regulates the optical output power from the laser. Two user-accessible input level-control adjustments enable you to independently adjust the transmitter input levels + 2 to

13 dB from an input level of 15 dBmV. All transmitter status-monitor information is available at the digital return receiver.

To facilitate easy upgrades, the DS-SG2-DRT-2X/A fits the same footprint and has the same set-up levels as the analog return transmitters.

Figure 5-23 illustrates a block diagram of the DS-SG2-DRT-2X/A:

Figure 5-23

DS-SG2-DRT-2X/A

Return

band RF 5-42 MHz

 

 

Anti-

 

RF

 

A/D

 

 

 

 

 

 

 

aliasing

 

 

 

 

 

 

 

 

 

XFMR

converter

 

 

 

Serial bit

Digital

 

 

LPF

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CATV

 

 

 

 

 

 

 

 

stream

lightwave to

 

 

 

 

 

 

 

 

@2.5 Gbps

SG2 output

gain block

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Transmit

signal

XOprocessing Serializer logic

Return

band RFOptical transmitter module 5-42 MHz

 

 

Anti-

 

RF

 

A/D

 

 

aliasing

 

 

 

 

 

XFMR

 

converter

 

 

LPF

 

 

 

 

 

 

 

 

 

 

 

XO

CATV

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

gain block

 

 

 

 

 

 

 

 

Figure 5-24 illustrates the DS-SG2-DRT-2X/A and attached cable:

Figure 5-24

DS-SG2-DRT-2X/A

RF INPUT B

 

 

 

 

 

Digital Transmitter

 

 

 

 

 

 

 

 

 

STATUS DS-SG2-DRT-2X/A

INPUT

 

 

 

 

 

1310 DFB

B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Test

 

 

 

Test

Point

 

 

 

Point

 

 

 

 

A

 

 

 

B

You can gain access to test point A through the transmitter test cable MCX-F (DS-SG2-DRT-TC, P/N 476803-001).

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 Installation E r a t i o nSpecification s Torque Specifications Abbreviations and AcronymsSG2-LR Tables N t e n t s Section SG 2000 closedFeatures include SG 2000 openUsing this Manual Related DocumentationBold type Document ConventionsIf You Need Help Calling for Repairs Mounting Holes HousingSG 2000 housing dimensions front and side view Port Locations Port locationsHousing gaskets GasketsPower Supply SG2-PS2 power supplyConfiguration Network MonitoringTo suit system requirements the RF chassis cover. notation Signal flow diagram Forward PathE r v i e w SG2-LR receiver functional diagram SG2-LR ReceiverModel Description Analog Return PathAnalog Return Transmitters Analog return transmittersSG2 transmitter block diagram JXPDigital Return Path Digital return transmittersDS-SG2-DRT-2X/A Level Control Options and AccessoriesOptions and accessories Model Description FunctionSG2 SG2-SBSG2-PS2 SG2-FEGain Selection Optical input versus 750 MHz gain10 illustrates the gain option selection chart for 870 MHz Optical input versus 870 MHz gainTilt Selection Relative level dB versus 750 MHz slope 77 channelsSG2 870 MHz Slope Chart Analog Channels, 220 MHz Digital Relative level dB versus 870 MHz slope 94 channelsSG2 870 MHz Slope Chart Analog Channels, 120 MHz Digital Relative level dB versus 870 MHz slope 110 channelsN 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 Service cable connection and compression fitting Splicing FiberInstallation Strand Wire Mounting Mounting bracket-front viewMounting bracket-rear and side views Center conductor length Coaxial CablesFiber Cables Housing lid and fiber spool tray Fiber spool tray Installation Forward Path RF Configuration Single Receiver ModeRedundant receiver Redundant Receiver ModeBroadband/Narrowcast Mode Broadband/narrowcastAB Override Functionality OverrideStatus Monitor/Manual Control Operation Status monitor/MCB operationSplit return Analog Return Path RF ConfigurationRedundant return RF chassis and location of the SG2-RPM/C or SG2-RPM/S board Digital Return Path RF Configuration DS-SG2-DRT/A redundant returnDS-SG2-DRT-2X/A split return DS-SG2-DRT-2X/A redundant returnRemoving SG 2000 Optical Modules Installing SG 2000 Optical ModulesSG 2000 Optical Modules Cleaning the Optical Connector SG2 LR Optical ReceiverFeature Description Test-point voltage versus optical power 0.3Wavelength Selection Jumper Wavelength selection jumperSG2 Ifpt Optical Transmitter FeatureDescriptionSG2-IFPT features SG2 FPT Optical Transmitter Transmitter enableSG2-FPT features SG2-DFBT features SG2 Dfbt Optical TransmitterSingle red LED that lights if the hybrid current is outside SG2-DFBT/3 features SG2 DFBT/3 Optical TransmitterSG2-EIFPT features SG2 Eifpt Optical TransmitterDS SG2 DRT/A Digital Return Transmitter DS-SG2-DRT/AFeature DS-SG2-DRT/A featuresDS SG2 DRT 2X/A Digital Return Transmitter DS-SG2-DRT-2X/ADS-SG2-DRT-2X/A features DS-SG2-DRT-2X/A cable connector DS-SG2-DRT-2X/A installed in SGDS-SG2-DRT-2X/A second RF input cable connection SG2-PS Power SupplySG2-PS power supply Status Monitoring Parameter DescriptionManual Control Board Description FunctionPotentiometers ICS1 Alarm test pointDB test point Through ICS4Off Ingress ControlState Description Table A-2 Station RF characteristics Parameter SpecificationTable A-1 SG 2000 optical characteristics Appendix aParameterSpeci fic ation Parameter Table A-5 SG2-IFPT RF specificationsTable A-6 SG2-FPT RF specifications Table A-7 SG2-DFBT RF specifications Table A-8 SG2-DFBT/3 RF specificationsTable A-9 SG2-EIFPT RF specifications Table A-10 SG2-DRT/A RF specificationsMinimum Optical Model Output Power DBm Table A-11 SG2-DRT-2X/A RF specificationsOption Watts ac Amps Power @90V @60V @52V @44V Table A-15 SG2-87 performance, with 94 channels Channels Link Launch SystemTable A-14 SG2-75 performance, with 77 channels Table A-16 SG2-87 performance, with 110 channelsTorque Fastener Screw Size Wrench Size In-lbs Ft-lbs DBmV DBcDBm MHzNational Television Standards Committee Return for service authorizationSnap connector Optical modulation indexMgbi