Cable Television System and CATV Architecture

Chapter 1: General Provisions

• Introduction (1.1)

  • The PRC Board of Electronics Engineering created the Electronics Code on Cable TV Systems due to the increasing demand for broadband and the growth of cable TV in the country.

• Purpose (1.2)

  • The code provides specifications, installation guidelines, procedures, and measurements to ensure quality TV signals and reliable cable TV facilities.

  • It also aims to protect other communication utilities from interference.

• Scope (1.3)

  • The code covers specifications for systems, installation, cabling, operating parameters (analog and digital TV, cable internet), grounding, cable specifications, and testing procedures.

  • It does not cover the brand or model of equipment.

• Units (1.4), Authority (1.5), Enforcement (1.6), Compliance Notation (1.7)

  • These sections are mentioned but not detailed in the transcript.

• Permits and Inspection Certificates (1.8)

  • An Electronics Permit is required before starting work.

  • An applicant must obtain an Electronics Permit from the Local Building Official for commercial buildings, requiring the service of a Professional Electronics Engineer (RA 9292).

• Requirements for Electronics Permit (1.8.1)

  • The Electronics Permit must include:

    • Applicant

    • PECE who signed and sealed electronic plans and specifications

    • PECE and/or ECE in charge of cable installation and electronic works

    • Building/lot owner

    • Building official

• Plans and Specifications (1.9)

  • Contents of the plan should include:

    • Location and site plans

    • Legends and symbols

    • General notes and specifications

    • Floor plan of headend facility

    • Cable TV distribution layout

    • One-line diagram of head-end system

    • One-line diagram of Distribution system

    • Standard title block

• Definition of Terms (1.10)

  • Refer to Section 1.10 for definitions.

Chapter 2: Service Entrance Facility

• Scope (2.1)

  • The service entrance facility includes aerial or underground installations with conduits, pull boxes, and cabinets.

  • It extends from the outside plant to the main service box of the building, applying to all multi-dwelling units (MDU) requiring structured cabling.

• Aerial Entrance (2.2)

  • Minimum Clearances (2.2.1):

    • Vertical Clearances:

      • Roads, streets, alleys, non-residential driveways, parking lots: $5.5 \text{ meters } (18 \text{ feet})$

      • Residential driveways: $4.7 \text{ meters } (15.5 \text{ feet})$

      • Sidewalks and other pedestrian traffic areas: $3.5 \text{ meters } (11.5 \text{ feet})$

      • Railroad tracks: $7.3 \text{ meters } (24 \text{ feet})$

      • Over roofs not accessible to pedestrians: $1 \text{ meter } (3 \text{ feet})$

      • Over balconies and roofs accessible to pedestrians: $3.2 \text{ meters } (10.5 \text{ feet})$

    • Horizontal Clearances:

      • To walls, projections, windows, balconies, and areas accessible to pedestrians: $1.4 \text{ meters } (4.5 \text{ feet})$

    • Horizontal and Vertical Clearances:

      • Signs, chimneys, billboards, radio and television antennas, and other installations not classified as buildings or bridges: $1 \text{ meter } (3 \text{ feet})$

      • Light or power service drops: $30 \text{ cm } (12 \text{ inches})$

      • Lightning Conductors: $1.8 \text{ meters } (6 \text{ feet})$

  • Avoid aerial or cable trespass (crossing neighboring property lines with the drop cable) (2.2.2).

• Aerial Entrance Installation (2.2)

  • Properly place the aerial cable on the nearest pole before attachment.

  • Locate the building attachment on the same side as the electrical utility line for an unobstructed run.

  • The entrance cable can be directly attached to the building with proper hardware and fixtures.

  • Use house hooks (P-hook, J-hook, Oval eye nut) to attach the cable to the building.

  • Ensure the house hook is screwed completely into a solid material of the building.

  • Do not attach the cable to rain gutters, power conduits, or other obstructions.

  • If the building is more than $30 \text{m}$ from the utility pole, the building owner must provide a private pole.

• Underground Entrance (2.3)

  • Select the shortest logical route for entrance conduits between the CATV provider and the building's main service pull box.

  • Bury underground conduits at least $600 \text{ mm}$ below the ground.

  • Avoid $90^\circ$ bends in conduits.

  • Install handholes for underground service conduits running more than $50 \text{m}$.

  • For FTTH installations, attach fiber slack management outside the building before distribution.

• Service Entrance Cable (2.4)

  • Can be either coaxial or fiber optic cable.

  • Use a minimum of 0.500 coaxial cable, solid Al, 75 ohms from the outside plant to the building's service entrance box.

  • When required, install a fiber optic cable from the outside plant to the service entrance pull box.

• Service Entrance Pull Box (2.5)

  • Install a service entrance pull box on the building wall when required.

  • The center of the cabinet should be $1.5 \text{m}$ from the ground.

  • Service Entrance Cabinet inside dimensions: $815 \text{ mm (H) x } 610 \text{mm (W) x } 305 \text{ mm (D)}$, AWG #16.

• Sample Service Entrance Layout

  • Diagrams are provided for:

    • Service entrance of multi-dwelling units, aerial, coaxial (Drawing Code C02-001)

    • Service entrance of multi-dwelling units, aerial, fiber (Drawing Code C02-002)

    • Service entrance of single-dwelling units, aerial, coaxial (Drawing Code C02-005)

    • Service entrance of single-dwelling units, aerial, fiber (Drawing Code C02-006)

    • Service entrance of multi-dwelling units, underground, coaxial (Drawing Code C02-003)

    • Service entrance of multi-dwelling units, underground, fiber (Drawing Code C02-004)

Chapter 3: Backbone Distribution System

• Scope (3.1)

  • The backbone cabling system interconnects entrance facilities, the headend equipment room, and the horizontal distribution system within the building.

  • Includes backbone cables, RF amplifiers, optical nodes, optical line termination, power supply, network access point, cable modem termination system, and optical distribution frame.

• Main Backbone Cabling Components (3.1)

  • Cable pathways.

  • Connecting hardware (patch panels, connecting blocks, interconnections, or cross-connections).

  • Backbone wiring (optical fiber, coaxial, twisted-pair copper, or a combination).

  • Necessary support facilities, if needed.

• Backbone Cables (3.2)

  • Backbone cabling is also referred to as vertical cabling.

  • Wiring can be coaxial, twisted pair copper, or optical fiber.

• Recognized Cables for Backbone Distribution System (3.2)

  • Vertical Cables:

    • .500 Coaxial Cable

    • Fiber Optic Cable (Single-mode)

    • Fiber Optic Cable (Multimode 50/125 or 62.5/125 μm)

    • Category-6 Copper Cable (UTP, SCTP)

  • Horizontal Cables:

    • .500 Coaxial Cable

    • Fiber Optic Cable (Single-mode)

    • Fiber Optic Cable (Multimode 50/125 or 62.5/125 μm)

    • Category-6 Copper Cable (UTP, SCTP)

• Conduits (3.3)

  • Service Entrance Conduit Size (Inside Diameter) and Type:

    • Provider to Service Entrance Pull Box: $2 \text{ x } 100 \text{ mm}$, PVC or IMC

    • Service Entrance Pull Box to Main Pull Box: $2 \text{ x } 50 \text{ mm}$, PVC or IMC

    • Riser (Vertical-Backbone): $2 \text{ x } 50 \text{ mm}$, PVC or IMC

    • Feeder (Horizontal-Backbone): $1 \text{ x } 50 \text{ mm}$, PVC or IMC

  • PVC can be exposed or embedded; IMC conduit is for surface installation.

• Pull Boxes (3.4)

  • Pull Box (PB) Type, Minimum Sizes (Height x Width x Depth), Gauge, and Notes:

    • Pedestal Box: $915 \text{mm x } 610 \text{mm x } 305 \text{mm}$, #16. A 220 Vac electrical outlet should be provided; installed at the basement, equipment room, wall space, for access node, trunk amplifier, network access point, OLT (optical line terminal).

    • Main Pull Box: $1220 \text{mm x } 915 \text{mm x } 305 \text{mm}$, #16. Installed at equipment room, wall space, hallway ceilings, for extender amplifier, network access point.

    • Distribution Pull Box: $813 \text{mm x } 508 \text{mm x } 305 \text{mm}$, #18. Installed along hallway ceilings. For line splitters, couplers, and tap-offs.

    • Splice Pull Box: $610 \text{mm x } 407 \text{mm x } 305 \text{mm}$, #18.

Chapter 4: Horizontal Distribution System

• Recognized Cables (4.1)

  • RG-6 coaxial cable (single-shield, 90% braid, 75 ohms)

  • Single-mode fiber optic cable

  • Multi-mode fiber optic cable 50/125µm

  • Cat6 copper cable

• Horizontal Distribution Pathways (4.2)

  • Junction box

  • Conduit pathways

  • Cable tray

  • Space cable supports

  • Ceiling conduits and cable trays

  • No splices in cables between termination points.

• Differences Between Backbone and Horizontal Cabling (4.2)

  • Areas covered: Backbone runs throughout floors or to different buildings; horizontal is contained to one floor near the telecommunications room.

  • Structural requirements: Differ due to different installation and usage.

  • Fire ratings and standards: Separate for each type of cabling.

• Coaxial Cable Infrastructure (4.3.1)

  • Channel Loading, Frequency, and Maximum Length of Horizontal Coaxial Cable (at $30 ^\circ C (86 ^\circ F)$) for One, Two, Four, and Eight Outlets:

    • Analog, NTSC, 6MHz - 250 MHz:

      • 343 m, 257 m, 171 m, 81 m

    • 26 - 350 MHz:

      • 297 m, 223 m, 149 m, 70 m

    • 43 - 450 MHz:

      • 249 m, 182 m, 117 m, 56 m

    • 60 - 550 MHz:

      • 221 m, 158 m, 102 m, 32 m

    • 76 - 750 MHz:

      • 188 m, 134 m, 87 m, 15 m

    • 110 - 870 MHz:

      • 174 m, 124 m, 72 m, 14m

    • 130 - 1002 MHz:

      • 162 m, 116 m, 67m, 13m

• Copper Cable Infrastructure (4.3.2)

  • Maximum Lengths Using 24 AWG [0.51 mm (0.020 in)] UTP/SCTP Patch Cords and 26 AWG [0.41 mm (0.016 in)] SCTP Patch Cords.

  • Horizontal (H), Work Area Cable (W), Combined (C) Lengths Table:

    • H = 90 (295): W = 5 (16), C = 10 (33) for 24 AWG; W = 4 (13), C = 8 (26) for 26 AWG

    • H = 85 (279): W = 9 (30), C = 14 (46) for 24 AWG; W = 7 (23), C = 11 (35) for 26 AWG

    • H = 80 (262): W = 13 (44), C = 18 (59) for 24 AWG; W = 11 (35), C = 15 (49) for 26 AWG

    • H = 75 (246): W = 17 (57), C = 22 (72) for 24 AWG; W = 14 (46), C = 18 (59) for 26 AWG

    • H = 70 (230): W = 22 (72), C = 27 (89) for 24 AWG; W = 17 (56), C = 21 (70) for 26 AWG

• Fiber Optic Cable Infrastructure (4.3.3)

  • Point to Point Fiber Horizontal Cabling

  • Blow Fiber Horizontal Cabling

  • Mid-Span Riser Horizontal Cabling

Chapter 5: Work Area

• Scope (5.1)

  • Specifications from subscriber outlet to subscriber terminal.

• Design Considerations (5.2)

  • At least one TV outlet box per room.

  • Outlet Box Dimensions:

    • L (Length): $68.8 \text{ mm } (2.71 \text{ in.}) \pm 1.02 \text{ mm } (0.040 \text{ in.})$

    • H (Height): $35.1 \text{ mm } (1.38 \text{ in.}) \pm 0.90 \text{ mm } (0.035 \text{ in.})$

    • T (Depth): $1.40 \text{ mm } (0.055 \text{ in.}) \pm 0.64 \text{ mm } (0.025 \text{ in.})$

    • R (Corner Radius): $4.06 \text{ mm } (0.160 \text{ in.}) \text{ max}$

    • C (Distance to 1st Obstruction): $30.5 \text{ mm } (1.2 \text{ in.}) \text{ min}$

• Work Area Design Considerations (5.2)

  • Wall plates with 75 ohms barrel splice “F”, both ends 3/8”-32 threads per inch, mounted in the center.

  • TV outlet box $15 \text{cm}$ apart from electrical outlet at the same level from the floor.

  • One meter minimum length of patch cord.

  • Coaxial patch cord: RG-6, single-shield, 90% braid.

  • RG-6 coaxial patch cord with compression type-F connector.

  • Cat 5e or Cat6 Cu wire patch cord.

  • Fiber optic patch cord with FC, LC, SC, or ST connectors.

Chapters 6-12

• Chapter 6: Outside Plant System

  • Scope, pole attachment, clearances, installation guidelines, recognized cables, recognized connectors.

• Chapter 7: Headend (Core) System

  • Scope, tower/antenna/satellite dish, headend facility, recognized cables and connectors.

• Chapter 8: Technical Operating Parameters

  • Scope, analog transmission, digital transmission.

• Chapter 9: Signal Leakage

• Chapter 10: Grounding and Bonding

  • Purpose, effective ground path, common grounding electrodes, general guidelines.

• Chapter 11: Cables and Connectors

  • Purpose, scope, hardline coaxial cable (75 ohms), braided coaxial cable (75 ohms), copper cable (UTP), fiber optic cable, RF connector and adapter, jack.

• Chapter 12: Signal Testing

  • Scope, coaxial cable, fiber optic cable.

CATV Architecture

• CATV Definition

  • Community Antenna Television: A system using a central antenna to broadcast TV signals to multiple viewers via coaxial cables.

  • Cable Television: Distribution of TV programming to paying subscribers via cable networks.

• CATV Architecture Frequencies

  • United States: $54 \text{ MHz}$ to $1002 \text{ MHz}$.

  • Philippines: $54 \text{ MHz}$ to $806 \text{ MHz}$.

  • Digital Television: $6 \text{ MHz}$ channel.

  • Set-top box CATV: ($5-1002$) MHz.

• CATV Components and Topology

  • Drop cable, taps, subscribers.

  • Coaxial cable, fiber cable.

  • Optical to electrical converter.

  • HFC (hybrid fiber coax) segment.

  • Tree and branch topology.

  • Hybrid Fiber Coax (HFC) – downstream and upstream, dual path approach.

  • Channels, PPV, VOD, Subscribers.

• SONET and FTTF

  • SONET (Synchronous Optical Network) ring architecture.

  • FTTF (Fibre to the Feeder): Fiber serves customers; only those watching VOD use a particular channel.

  • Ring: 96 strands of optical fibers from head-end to a first primary hub.

• Head End

  • Location where all signals are received and gathered for distribution.

• CATV Head-End Functions

  • Signal Reception

  • Signal Processing: Demodulation, decoding, error correction.

  • Channel Selection and Multiplexing: Allows multiple channels over a single cable.

  • Analog to Digital Conversion: Improves picture and sound quality.

  • Encryption and Conditional Access: Protects content and manages subscriptions.

  • Insertion of Local Content and Advertisements

  • Signal Amplification and Distribution.

• Geostationary Satellite

  • Located at $36,000 \text{ km}$.

• Primary Hubs

  • Located at or near the headend.

  • Aggregates signals, processes them, and distributes them.

  • Secondary hubs may exist in larger networks closer to subscribers.

  • Racks of equipment with battery-backed PS, AC, and remote monitoring.

• Hybrid Fibre Coax (HFC) Architecture

  • Head End -> Primary Hub (Optical Fibre Ring) -> Optical Node -> Trunk Coax -> Line Extender -> Tap -> Subscribers

• Optical Node

  • Converts optical signals to electrical signals (and vice versa).

  • Optical to Electrical Conversion: For processing and distribution over coaxial cable.

  • Amplification: Maintains signal strength and quality.

  • Signal Processing: Filtering unwanted frequencies, adjusting signal levels.

  • Electrical to Optical Conversion: In the upstream, for transmission over fiber optic network.

  • Remote Monitoring and Management: Monitors signal quality, adjusts settings, performs maintenance tasks.

• Optical Node Distribution

  • Each optical node drives up to 6 coax cable trunks (feeders).

  • Each trunk drives up to 6 distribution lines.

• Trunk Cabinet

  • Weatherproof enclosure housing equipment and components of the distribution system.

  • Located outdoors, along the cable TV network.

  • Serves as a distribution point.

• Trunk Cabinet Components

  • Distribution Amplifier

  • Directional Coupler

  • Power Supply

  • Signal Filters

  • Monitoring and Control Equipment: Allows remote monitoring and adjustments.

• Coax Cables and Connectors

  • Rigid/Hardline Coax: CATV Trunk Coax, CATV Distribution Line Coax.

  • Flexible Coax: Cable TV Coax.

• CATV Power Supply

  • Pole-mounted.

    • Analogue galvanometer-type ammeter to show output current and a 15 amp output fuse.

    • Test button to put batteries on-line.

    • Pascaline-type meter to show total hours for which the batteries were being used.

    • Green indicator to show line voltage is being received.

    • Red indicator to show local power failure, and the batteries are providing power.

  • The power supply has an expansion chassis.

  • The grey plastic conduit brings the 220V AC.

  • The thick black cable carries the 60 v AC power at up to about 15 amps.

• CATV Distribution Line Extender

  • Extends the reach of the signal over long distances.

  • Signal Amplification

  • Compensation for Losses

  • Signal Quality

  • Extended Reach.

  • Bi-directionally amplifies the signal on the coaxial cable and is powered from the 60 v AC power on the same coaxial cable.

• CATV Distribution Line Extender - Terminator

  • Terminator, which is basically a $75 \Omega$ resistor, is screwed onto unused ports, as these prevent outside noise from entering the cable plant, and eliminate reflections.

• CATV Aerial Line Extender

  • Has a single input and a single output.

  • The output is directly connected to a four-port tap.

  • There is a line extender every four or five taps.

• CATV Tap

  • Eventually, you get to the end of the CATV distribution line, and a 75 ohm termination resistor must be installed on the unused downstream distribution line port.

• CATV Demarcation Box

  • The black cable brings the signal from the CATV company, and a splitter (inside the box) then provides an output.

• Signal Splitter

  • The top connection is where the input (from the cable TV company) goes, and the two outputs are at the bottom.

• Gilbert Locking Terminator

  • It looks line an F-type connector

• Notch Filter

  • A NOTCH FILTER prevents a specific range of frequencies from passing through