Motorola SG 2000 operation manual E r v i e w

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O v e r v i e w

To assess fiber link status, the optical-power monitor circuit is active at all times (even when the receiver is disabled). An integrated optical bulkhead connector and module link status indicators enhance fiber management and reduce troubleshooting time. The receiver module is fully compatible with the status monitor transponder for remote monitoring of key module and link performance parameters.

Several plug-in boards are available to configure the SG 2000 lid board for single, redundant, or narrowcast receiver arrangements. A low-noise pre-amplifier hybrid amplifies the signal to a level suitable for connection to the RF chassis.

An SG2-FRB flatness board, at the input to the RF chassis, compensates for hybrid and accessory response signatures. A variable attenuator circuit enables fine adjustment of the output level, and is driven either by the standard thermal control unit (TCU) or optional ADU pilot automatic gain control (AGC) module to compensate for temperature and input level variations.

The MDR-*/* circuit board provides a fixed linear equalizer for either 750 MHz or 870 MHz. This equalizer comes in numerous values to support various levels of output tilt. The MDR board also compensates for the low frequency roll-off inherent in plug-in diplexers.

A driver-hybrid amplifies the signal to a sufficiently high level to feed up to four power-doubling output stages. These output hybrids can be either conventional silicon or premium gallium arsenide types for even higher station output at low distortion. Plug-in facilities are available ahead of each output stage for individual equalizer boards. These can be installed to customize the tilt for the various ports. At one output, a minus 16 dB directional coupler provides signal to the optional ADU and status-monitor modules. This signal is used only when either or both of these options is installed. It is not necessary to terminate the coupler output when neither option is present.

Minus 20 dB directional test points are available at various points in the signal paths of the node. Because these test points are 75-ohm source impedance, special test probes are not required.

Model JXP-* attenuator pads are used for adjusting signal levels within the signal path. The unit is shipped with JXP-ZX versions installed.

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 ManualDocument Conventions If You Need HelpBold type Calling for Repairs Housing SG 2000 housing dimensions front and side viewMounting 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 Coaxial Cables Fiber 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 OperationAnalog Return Path RF Configuration Redundant returnSplit 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 returnInstalling SG 2000 Optical Modules 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 JumperFeatureDescription SG2-IFPT featuresSG2 Ifpt Optical Transmitter Transmitter enable SG2-FPT featuresSG2 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 ICS4Ingress Control State DescriptionOff Table A-1 SG 2000 optical characteristics Parameter SpecificationTable A-2 Station RF characteristics Appendix aParameterSpeci fic ation Table A-5 SG2-IFPT RF specifications Table A-6 SG2-FPT 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
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