Motorola SG 2000 Digital Return Path RF Configuration, DS-SG2-DRT/A redundant return

Page 71

O p e r a t i o n

5 - 7

4Remove the eight screws that secure the SG2-RPM/C board to the chassis. Remove the SG2-RPM/C board. To assist in removing the SG2-RPM/C board, the handle is cantilevered so that pulling up on the handle extracts the board from the chassis.

5Remove the 5-pin power connector that provided dc power to the SG2-RPM/C board.

6Install the SG2-RPM/S board by reversing the above procedure. Do not re-install the 5-pin power connector as the SG2-RPM/s does not require nor accept it.

Digital Return Path RF Configuration

If you are using a single DS-SG2-DRT/A transmitter, it must be installed in the optical transmitter A position as illustrated in Figure 3-1. A JXP-5A (5 dB) pad is installed in the pad facility at the A transmitter location. A JXP-15A (15 dB) pad must also be installed in the pad facility at the B transmitter location to terminate the signal from the return-path-module combiner board (SG2-RPM/C).

For single return applications, the SG2-LIDB distributes an individual RF signal from the RF chassis to transmitter A. Installing an optional second transmitter (B) provides return redundancy as illustrated in Figure 5-10. Installing a redundant B transmitter also requires that you change the pad at that location to a JXP-5A.

Figure 5-10

DS-SG2-DRT/A redundant return

LID

	TP
Optional
Optional			JXP
transmitter
transmitter
A
A

Transmitter

BJXP

TP

BASE

Status

monitor

SG2-RPM/C

SG2-RPLPF

TP

H

LP filter

Ingress

JXP

L

TP

Bulkhead connector for dc power

SG 2000 Installation and O peration Manual

Image 71

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 ManualBold type Document ConventionsIf You Need Help Calling for Repairs Mounting Holes HousingSG 2000 housing dimensions front and side view 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 PathAnalog Return Transmitters Model DescriptionJXP SG2 transmitter block diagramDigital return transmitters Digital Return PathDS-SG2-DRT-2X/A Model Description Function Options and AccessoriesOptions and accessories Level ControlSG2-FE SG2-SBSG2-PS2 SG2Optical 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 Center conductor length Coaxial CablesFiber Cables Housing lid and fiber spool tray Fiber spool tray Installation Single Receiver Mode Forward Path RF ConfigurationBroadband/narrowcast Redundant Receiver ModeBroadband/Narrowcast Mode Redundant receiverOverride AB Override FunctionalityStatus monitor/MCB operation Status Monitor/Manual Control OperationSplit return Analog Return Path RF ConfigurationRedundant 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 returnRemoving SG 2000 Optical Modules Installing SG 2000 Optical ModulesSG 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 Optical Transmitter FeatureDescriptionSG2-IFPT features SG2 FPT Optical Transmitter Transmitter enableSG2-FPT features 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 connectorDS-SG2-DRT-2X/A second RF input cable connection SG2-PS Power SupplySG2-PS power supply Parameter Description Status MonitoringDescription Function Manual Control BoardThrough ICS4 Alarm test pointDB test point Potentiometers ICS1Off Ingress ControlState Description Appendix a Parameter SpecificationTable A-1 SG 2000 optical characteristics Table A-2 Station RF characteristicsParameterSpeci fic ation Parameter Table A-5 SG2-IFPT RF specificationsTable A-6 SG2-FPT RF specifications 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-16 SG2-87 performance, with 110 channels Channels Link Launch SystemTable A-14 SG2-75 performance, with 77 channels Table A-15 SG2-87 performance, with 94 channelsTorque Fastener Screw Size Wrench Size In-lbs Ft-lbs MHz DBcDBm DBmVOptical modulation index Return for service authorizationSnap connector National Television Standards CommitteeMgbi