Motorola SG 2000 operation manual R w a r d P a t h P a d d i n g

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B e n c h S e t u p

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F o r w a r d P a t h P a d d i n g

The pad values, presented in Table 3-2 or Table 3-3, serve as a starting-point reference for typical installations. While this chart is prepared specifically for 77 channel loading and the low-gain option, the difference for 110 channel loading is approximately 1 to 2 dB less.

It may be necessary to select a JXP value 1 dB or 2 dB lower for the receiver output (amplifier input) pad than shown in Tables 3-2 or 3-3. This may be required to balance the four outputs for level, which can only be done with the output stage pads. If the optical levels are high, the transmitter’s optical modulation index (OMI) is higher than specified, or if the target output is low, the output pad may already be a non-zero value as indicated in Tables 3-2 or 3-3. To ensure that the target output level is reached on the lowest-level output branch, select input pads of at least 1 dB value for the output pad.

Pads values shown are minimum values expected. If more padding is needed, increase the receiver pads to a maximum of 15 dB and place the rest of the required attenuation at the interstage pad facility.

S G 2 0 0 0 I n s t a l l a t i o n a n d O p e r a t i o n M a n u a l

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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 ReceiverAnalog Return Path Analog Return TransmittersModel Description Analog return transmittersSG2 transmitter block diagram JXPDigital Return Path Digital return transmittersDS-SG2-DRT-2X/A Options and Accessories Options and accessoriesLevel Control Model Description FunctionSG2-SB SG2-PS2SG2 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 Mode Broadband/Narrowcast ModeRedundant receiver 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 FunctionAlarm test point DB test pointPotentiometers ICS1 Through ICS4Off Ingress ControlState Description Parameter Specification Table A-1 SG 2000 optical characteristicsTable A-2 Station RF 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 Channels Link Launch System Table A-14 SG2-75 performance, with 77 channelsTable 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 DBc DBmDBmV MHzReturn for service authorization Snap connectorNational Television Standards Committee Optical modulation indexMgbi