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Activating The Modern Return Plant Presented By Michael E. McCracken Eastern Show ‘96 Presented By Michael E. McCracken Eastern Show ‘96
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2 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Topics
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3 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Return Path Overview AM Fiber LinkCoaxial DistributionHeadendTransport Drop
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4 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant The Forward & Return RF Spectrum 5MHz750MHz Return Forward 40MHz54MHz System Split 2 3 4 5 6 …..
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5 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Two-Way Amplifier 54-750MHz 5 - 40MHz 54-750MHz Forward Amplifier Return Amplifier Diplex Filter C H L H C L From/To Headend To/From Subscriber
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6 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Diplex Filter Crossover 5MHz750MHz Return Forward 40MHz54MHz Crossover Amplitude
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7 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant AM Fiber Link Diplex Filter Forward ReceiverForward Transmitter Return ReceiverReturn Transmitter Forward Fiber Return Fiber AM Optical Node Hub or Headend To/From Distribution System
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8 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant RF Impulse-Pay-Per-View AM Fiber LinkCoaxial Distribution Drop Settop Terminal HeadendTransport Control System
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9 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant RF-IPPV Frequency Allocation 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz v v 15.45MHz17.75MHz
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10 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant RF-IPPV Bandwidth Utilization 15.45 MHz17.75 MHz 2.3MHz 23 Channel Slots 100kHz
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11 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant High-Speed Cable Modems AM Fiber LinkCoaxial Distribution Drop Settop Terminal HeadendTransport Interface
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12 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Modem Frequency Allocation 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz
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13 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Modem Bandwidth Utilization 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz 1 MHz
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14 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Telephony Telephone Interface AM Fiber LinkCoaxial Distribution Drop HeadendTransport Interface
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15 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Telephony Frequency Allocation 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz 50 kHz 1 Voice Channel = 50kHz
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16 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Telephony Bandwidth Utilization 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz 240 Channels in 12MHz
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17 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Status Monitoring Monitoring System AM Fiber LinkCoaxial Distribution Drop HeadendTransport
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18 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Status Monitoring Frequency Allocation 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz 29.8MHz Typical
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19 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Status Monitoring Bandwidth Utilization 5 MHz40 MHz29.8MHz 250 kHz
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20 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Interactive Services Video Server AM Fiber LinkCoaxial Distribution Drop HeadendTransport Digital Settop Terminal
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21 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Interactive Services Frequency Allocation One or more channels Frequency Agile 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz Signaling Channel
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22 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Interactive Services Bandwidth Utilization 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz 1.0 MHz
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23 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Current Bandwidth Utilization 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz RF-IPPV Telephony Cable Modem Status Monitoring Interactive Services
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24 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Proposed Bandwidth Allocation 5 MHz40 MHz10 MHz15 MHz20 MHz25 MHz30 MHz35 MHz RF-IPPV Telephony Cable ModemStatus MonitoringInteractive Services
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25 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Bandwidth Limitations 5MHz750MHz Return Forward 40MHz54MHz
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26 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Segmented Reverse Fiber Cable Coaxial Distribution Diplex Filter Reverse Fiber Tx Fiber Rx
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27 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Block Conversion Optical Receiver Optical Transmitter Block Converter Block Converter Combiner 54 MHz750 MHz Reverse Block 5 - 40MHz Reverse Block 5 - 40MHz Upstream Blocks 5 - 40 MHz 40 - 75 MHz 75 - 110 MHz 110 - 145 MHz 35 MHz 54075
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28 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant High-End Return 735 MHz Forward 50 MHz1 GHz Return 900 MHz
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29 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Thermal Noise Carrier-to-Noise Ratio Noise Energy RF Carrier
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30 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Noise Accumulation: Forward 12 45 3
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31 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Noise Accumulation: Return 1 2 3 4 5
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32 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Managing Thermal Noise Return TransmittersReturn Combining Network Noise
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33 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant RF Ingress HAM 40 M20 M15 M CB Land Mobile 40MHz Land Mobile Civil Air Patrol 5.0MHz Sub-Split Return Spectrum Potential Ingress Sources
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34 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Non-RF Ingress Power line conducted emissions and noise Household electric motor noise Industrial electric motor noise Electrical switches Electrostatic discharge
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35 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Ingress Causes Drop Reports of 70 to 90% caused by drops and house wiring. 10 to 30% caused by coaxial plant problems.
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36 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Drop Cable Transfer Impedance Frequency 0MHz1GHz 0 m /m 100 m /m Headend Quad 60/40 Quad 60% Braid Worse Better 50MHz
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37 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant RF Egress Potential for Harmful Interference HAM 40 M20 M15 M CB Land Mobile 40MHz Land Mobile Civil Air Patrol 5.0MHz Sub-Split Return Spectrum
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38 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Rules on Interference Concerned with “harmful interference” –Radio navigation –Safety of life and protection of property –Radiocommunication services System Operator must eliminate the problem “immediately” –Measures include service or even system shutdown Concerned with “harmful interference” –Radio navigation –Safety of life and protection of property –Radiocommunication services System Operator must eliminate the problem “immediately” –Measures include service or even system shutdown
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39 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Summary Bandwidth is limited and must be carefully managed Thermal Noise is a natural phenomenon and must be managed Ingress points must be located and eliminated on a continuous basis Egress must be tracked down and eliminated to prevent interference with radio communications Bandwidth is limited and must be carefully managed Thermal Noise is a natural phenomenon and must be managed Ingress points must be located and eliminated on a continuous basis Egress must be tracked down and eliminated to prevent interference with radio communications
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40 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Basic Network Headend End of line Far from Headend Large house Two outlets First tap Closer to headend Short drop Small house Three outlets
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41 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Headend Pad Modulator Combiner Same Amplitude RF Carriers To Distribution
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42 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Forward AM Fiber Links Forward Tx Forward Rx From HeadendTo Distribution Fiber Signal Input Signal Output
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43 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Forward Unity Transmission -24 +24 Condition Established Condition Repeated From Headend Gain = Loss Output Level Input Level 1234 +24 -24 0 +24 -24 0
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44 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Basic Forward Amplifier EQ Interstage Section -20dB Test -20dB Test Input Test Point Output Test Point PAD Input Amp Output Amp
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45 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Amplifier Spacing -24 +24 1 2 -19 +24 1 2 Obstacle (Water) Normal Spacing Short Spacing
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46 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Amplifier Pad Input Test Point Input Amp +24dB Desired Input = 11dBmV Input = 16dBmV 5 Attenuation 24dB - 19dB = 5dB Amplifier Output 11dBmV + 24dB = 35dBmV -19dB Amplifier Input 16dBmV - 5dB = 11dBmV
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47 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Amplifier Pad Application -24-20 +24 From Headend 1234 -22 5 -12 -11 Pad: 24 - 24 = 0 Input: 35 - 24 = 11 Forward Pad used to achieve same input level on all amplifiers +24 11dBmV 35dBmV Pad: 24 - 12 - 11 = 1 Input: 35 - 12 - 11 - 1 = 11 Pad: 24 - 20 = 4 Input: 35 - 20 - 4 = 11 Pad: 24 - 22 = 2 Input: 35 - 22 - 2 = 11
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48 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Forward Amplifier Equalizer EQ Interstage Section -20dB Test -20dB Test Input Test Point Output Test Point PAD Input Amp Output Amp
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49 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Attenuation vs. Frequency 520803201280 124816 4 x Frequency = 2 x Attenuation Attenuation Factor Frequency in MHz
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50 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Loss Ratio 50800 50800 Flat Test Signal Cable = 24dB at 800MHz 6dB 24dB
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51 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equalizer Attenuation Curve 50100200400800 Attenuation Frequency in MHz Equalizer Cable Equalizer + Cable
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52 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equalizer Function 6dB 50MHz100MHz200MHz400MHz800MHz 8.5dB 16.5dB 13dB 12dB 17dB 8dB 19dB 1dB Equalizer Attenuation 24dB 25dB Cable Attenuation 25dB
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53 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equalizer Function 50800 25dB 50800 6dB 24dB25dB Equalizer 24dB 800MHz Equalizer InputEqualizer Output Equalizer Reference Frequency
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54 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Pad and Equalizer Practice -24-20 +24 From Headend 1234 -22 5 -12 -11 Pad: EQ : Input: +24 11dBmV 35dBmV Pad: EQ : Input: Pad: EQ : Input: Pad: EQ : Input: Pad: EQ : Input: Includes EQ Loss
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55 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Transition to Tapped Feeder -24-20 +24 From Headend 123 4 -17 +24 11dBmV 35dBmV +30 35 - 17 = 18dBmV 18 + 30 = 48dBmV
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56 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equal Loss Signal Splitting -4 -2 48dBmV -4 Distribution System with equal loss taps 44dBmV38dBmV32dBmV26dBmV20dBmV14dBmV Unacceptable amplitude differences Inefficient signal distribution
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57 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equal Loss Distribution -2 48dBmV Distribution System with selectable attenuation 16dBmV Equal amplitude at all subscriber connections Equal attenuation to all subscriber connections Feeder amplitude preserved for additional distribution 322926232017 Attenuation: (5 x 1) + (5 x 2) + 17 = 32dB Amplitude: 48dBmV - 32dB = 16dBmv
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58 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Summary All signals aligned to common amplitude at Headend The Forward Fiber Link provides “transparent” transport The Coaxial Trunk system provides “Unity Transmission” The Coaxial Feeder provides equal distribution of available signal All signals aligned to common amplitude at Headend The Forward Fiber Link provides “transparent” transport The Coaxial Trunk system provides “Unity Transmission” The Coaxial Feeder provides equal distribution of available signal
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59 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Basic Return Network Headend End of line Far from Headend Large house Two outlets First tap Closer to headend Short drop Small house Three outlets Sources
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60 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Signal Combining Pad Modulator Combiner Same Amplitude RF Carriers To Distribution
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61 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Return Path as a Combiner Source Common Test Point Combiner Settops Objective: Achieve desired amplitude and quality at common test point. HFC Network
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62 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Signal Combining at the Home TV 1 TV 2 -5.5dB 75’ @ 1.67 = -1.25dB 35’ @ 1.67 = -.58dB 10’ @ 1.67 = -.17dB +55 dBmV +55 dBmV 123 49.3 48.9 48.3 +55 dBmV Cable Modem
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63 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Terminal Calibration TV 1 TV 2 -5.5dB 75’ @ 1.67 = -1.25dB 35’ @ 1.67 = -.58dB 10’ @ 1.67 = -.17dB +54 dBmV +54.4 dBmV 123 48.3 +55 dBmV Cable Modem
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64 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Combining in the Feeder Plant -.5 48dBmV 322926232017 Attenuation: (5 x 1) + (5 x.5) + 17 = 24.5dB Attenuation: 32dB Reverse Amplifier Input 1:16.0dBmV4:20.5dBmV 2:17.5dBmV5:22.0dBmV 3:19.0dBmV6:23.5dBmV 123456 1 2 3 4 5 6
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65 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Traditional Concept -.5 48dBmV 46.5dBmV 45dBmV 43.5dBmV 42dBmV 40.5dBmV 322926232017 Attenuation: (5 x 1) + (5 x.5) + 17 = 24.5dB Attenuation: 32dB Reverse Amplifier Input = 16dBmV 123456 654321 Terminal output adjusted to compensate for path conditions
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66 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Unity Loss in Return Path -.5 48 dBmV 48 dBmV 48 dBmV 48 dBmV 48 dBmV 48 dBmV 322926232017 Reverse Amplifier Input Uniform at 16.0dBmV Maximum output level for best carrier/interference ratio 0-1.5-3-4.5-6-7.5 123456 Return Path Pad Attenuation: 32dB Attenuation: (5 x 1) + (5 x.5) + 17 + 7.5 = 32dB
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67 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Splitters and DCs in the Return Path -.5 -8 -.5 48 dBmV 48 dBmV 48 dBmV 48 dBmV 48 dBmV 48 dBmV 322926232017 0-1.5-3-4.5-6-7.5 123456 -.5 48 dBmV 48 dBmV 48 dBmV 14118 -5.5-7-8.5 789 -.5 Total Attenuation always = 32dB Amplifier Input Always = 16dBmV 1 Values are arbitrary examples
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68 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Basic Reverse Amplifier EQ Interstage Section -20dB Test -20dB Test Input Test Point Output Test Point PAD Input Amp Output Amp Rvrs Amp Diplexer -20dB Test -20dB Test EQ PAD -20dB Rev Inj
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69 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Pads and EQs EQ Interstage Section -20dB Test -20dB Test Input Test Point Output Test Point PAD Input Amp Output Amp Rvrs Amp Diplexer -20dB Test -20dB Test EQ PAD -20dB Rev Inj
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70 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Pad Application -5 -8 +10 To Headend +10 -4 -2 +10 -5 A B Gain vs Attenuation Path A = 10 - (4 + 1) = 5dB Path B = 10 - (2 + 8) = 0dB Amplifier #3 Input 12 3 A B
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71 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Pad Application (con’t) -5 -8 +10 To Headend +10 -4 -2 +10 -5 AB Attenuation vs Gain Path A = 10 - (4 + 1 + 5) = 0dBmV Path B = 10 - (2 + 8 + 0) = 0dBmV Amplifier #3 Input 0dB Pad 5dB Pad 12 3 A B
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72 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Pad Exercise EQ PAD +10dB EQ PAD +10dB EQ PAD +10dB Reverse Amp A Reverse Amp BReverse Amp C -4dB -1dB -8dB -1dB
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73 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Unity Transmission -6 +6 Condition Established Condition Repeated To Headend Gain = Loss Output Level Input Level +6 -6 0 +6 -6 0 12 34
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74 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Equalizers EQ Interstage Section -20dB Test -20dB Test Input Test Point Output Test Point PAD Input Amp Output Amp Rvrs Amp Diplexer -20dB Test -20dB Test EQ PAD -20dB Rev Inj
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75 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Attenuation vs. Frequency 520803201280 124816 4 x Frequency = 2 x Attenuation Attenuation Factor Frequency in MHz
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76 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Cable Loss Ratio 50800 50800 Flat Test Signal Cable = 24dB at 800MHz 6dB 24dB
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77 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equalizer Attenuation Curve 510152040 Attenuation Frequency in MHz Equalizer Cable Equalizer + Cable
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78 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Equalizer Function 2.1dB 5MHz10MHz20MHz40MHz 3dB 4dB 4.3dB 2.7dB 4.9dB 1dB Equalizer Attenuation 6dB Cable Attenuation 7dB
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79 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Equalizer Function 540 7dB 540 2dB 6dB7dB Equalizer 6.0dB 40MHz Equalizer InputEqualizer Output Equalizer Reference Frequency
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80 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Pad and EQ Practice -6-5 +10 To Headend -5 -8 -2 Pad: EQ : Atten: +10 Pad: EQ : Atten: Pad: EQ : Atten: Pad: EQ : Atten: Pad: EQ : Atten: Includes EQ Loss
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81 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse AM Fiber Links Reverse Rx Reverse Tx To HeadendFrom Distribution Fiber Signal Output Signal Input
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82 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Summary All paths must have equal attenuation Reverse signals must be maintained at the highest possible levels 40MHz signals experience only about one fourth the cable attenuation of 750MHz signals Passive devices attenuate forward and reverse signals approximately the same All paths must have equal attenuation Reverse signals must be maintained at the highest possible levels 40MHz signals experience only about one fourth the cable attenuation of 750MHz signals Passive devices attenuate forward and reverse signals approximately the same
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83 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Early Return Path Application 2T9 Video/Audio returned to headend on Return Path channel Return Path Channel translated to Forward Path channel Subscribers view local video on Forward Path channel
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84 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Basic Alignment Technique Signal Source Technician 1 Injects calibrated test signal Selects Pads and EQs Technician 2 Informs Tech 1 of results
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85 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Improved Alignment Technique 2 Return Path signal displayed on analyzer Technician views analyzer display on TV and makes adjustments to Return Path Spectrum Analyzer Baseband Video Camera views analyzer display Camera output modulated to Forward Path channel Signal Source
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86 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Sweeping vs Balancing Balancing with two carriers Only two reference points visible Broadband Sweeping Hundreds of reference points
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87 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Sweep Equipment Headend Unit Field Unit
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88 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Typical Sweep Display 5MHz40MHz 5db/Div Ref Lvl +20dBmV
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89 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Return Path Activation Steps Install sweep system headend unit Configure sweep equipment Install and Align Reverse Fiber Link Install and Align reverse amplifiers in sequence, from first to last Install sweep system headend unit Configure sweep equipment Install and Align Reverse Fiber Link Install and Align reverse amplifiers in sequence, from first to last
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90 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Installing the 3ST Transmitter Combining Network Forward Laser Forward Laser Return Path Receiver Return Path Receiver Return Signal Break-out Diplex Filter H / L Fiber Out Fiber In out in Sweep Signal -10 to -12dB Telemetry Signal -5dB Input -10dBmV to +10dBmv
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91 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Configuring the 3ST Transmitter Enable Reverse Sweep Select Reverse Telemetry Carrier Frequency Create a Reverse Sweep Plan Select a Reverse Sweep Plan Enable Reverse Sweep Select Reverse Telemetry Carrier Frequency Create a Reverse Sweep Plan Select a Reverse Sweep Plan
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92 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Sweeping a Fiber Node Forward Receiver Forward Receiver Reverse Transmitter Reverse Transmitter LHLH Fiber In Fiber Out From System inout 3SR External RF In Forward Test Point Fiber node
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93 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Reverse Fiber Receivers Return Path Receiver Return Path Receiver Return Signal Break-out Diplex Filter H / L Fiber In in Return Path Receiver Return Path Receiver Fiber In Return Path Receiver Return Path Receiver Fiber In Return Path Receiver Return Path Receiver Fiber In Return Signal Combiner -8dB-11dB -0.5 +24dBmV +3.5dBmV
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94 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Inboard Test Points LHLH Coaxial Cable inout 3SR Forward Test Point LHLH Coaxial Cable Two-way Amplifier with Test Point Inboard of Diplex Filter
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95 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Outboard Test Points LHLH Coaxial Cable inout 3SR Forward Test Point NS-6 LHLH Coaxial Cable Two-way Amplifier with Test Point Outboard of Diplex Filter Wavetek Model 3ST Operating Guide Section 5.1.3
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96 GTS Enterprises, Inc. Wednesday, September 18, 1996 Activating the Modern Return Plant Summary Understand your Return Path application Know the design specifications Install and configure the sweep system headend equipment Align the Reverse Fiber Links for uniform receiver output Align the coaxial plant to have least impact on transmitted signals Understand your Return Path application Know the design specifications Install and configure the sweep system headend equipment Align the Reverse Fiber Links for uniform receiver output Align the coaxial plant to have least impact on transmitted signals
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