impact of repacking cory - national translator...
TRANSCRIPT
Impact of Repacking on FM and TV Stations
Presented by: Cory Edwards, Sales Manager
Impact of Repacking on FM and TV Stations
Presented by: Cory Edwards, Sales Manager
What’s Different This Time
Industry DynamicsWho stays?Who cashes in and gets out?Channel Sharing?Master Broadband Antennas?Do you have someone at your site that has done this?
(many have retired)
ManufacturesWho is left?They May Have limited or fewer resources?Installers are more limitedIndustry is older (retirees take knowledge)Fundamental changes in technology
Topics for Discussion
• Repack Overview
• Equipment Re-channelization – Antennas, Line, Inside RF
• Logistics and Installation
• Opportunities - Leased Facilities, FM System Upgrades
• What Can I do Now
TV Channels (stations) Received by County
1700 Full Power Stations in 210 Markets1700 Full Power Stations in 210 Markets
TV Repacking Impact ‐ Overview
20 Channels – 1/3 of Band, 550 Channels Minimum10 Channels – 1/6 of Band, 275 Channels Minimum
More Shared Facilities - Broadband Systems – Higher Wind loads- Opens up aperture for FM Upgrades
Distributed Transmission Systems, Gap Fillers, OFDM ?
Service interruption (or Reduction) on temporary basis, during build-out.TV stays on old channel during move to new. FM may need temporary aux system. = Additional tower loads
QUESTION 1: IS the repack going to happen ? Congress says ‘yes’ !
QUESTION 2: WHEN ? CANADA ? ATSC 3.0 ?
Antenna Considerations
SLOT ANTENNAS• High Power: Limited Bandwidth +/- 1 channel maybe• Low Power : +/- 5 Channels with relaxed specifications
BROADBAND PANELS• Hpol: Full Channel Bandwidth -typical
BB PANELS WITH VPOL • +/- 10 channels typical before Vpol varies more significantly
RF Components: UHF Retune or Replace?
Retune:o Waterloadso w/g miterso Directional couplerso Coax switcheso w/g switcheso Patch panels
Replace:o Mask filterso Magic teeo Combiners
Retune:o Waterloadso w/g miterso Directional couplerso Coax switcheso w/g switcheso Patch panels
Replace:o Mask filterso Magic teeo Combiners
Changing Channels
• Need to be on‐air with existing equipment while new is being installed
• Physical space issues
• Availability of RF talent to re‐tune & install components
• Some older equipment may not be supported– Example: 50000 series switches
• Transmission lines need to be measured at new channels
VHF RF Systems
• Mask Filters grouped ch 7-9 and
10-13
• All other components are
broadband
• Mask Filters grouped ch 7-9 and
10-13
• All other components are
broadband
Low Power UHF (< 5 kW) ?
All UHF filters band tunable since 2012
All other components are broadband
All UHF filters band tunable since 2012
All other components are broadband
Wind Load Comparison
UHF over UHF with radomes
2 UHFs STACKEDArea = 100 - 200 ft²
DTV/ANALOG with panel
(12 Bays)
4 Around. Area = 280 ft²
5 Around. Area = 420 ft²
FM - Opportunities
Move up on tower, Consolidate facilities, Save cost$Move up on tower, Consolidate facilities, Save cost$
FM Antenna Mounted on UHF Pole• Assume no structural compromise
• Rust, fatigue, extreme wind, etc…
• Assumes slot covers remain, Drag coefficient 0.08
• Old antennas built to 222‐C 50/33 psf• New antenna built to 222‐F 80 mph; 69 MPH with 0.5” ice
• Determine mast capacity in Wind Area
• Determine maximum allowable Antenna/Pole stresses
• Difference in wind area = largest antenna the mast can handle; length limits the # of bays
• Weight not a major concern
• Recommend 5 ft minimum between tower top and first bay
Mounting FM to VHF Antenna
VHFs may be Older than UHFs
Older Structural Code
Similar Analysis to UHFs, but…….
Elements Used for Climbing (may need pole steps)Clamp On (RCA) vs Welded (Harris)Telescoping Poles (FM Mounts)Lighting Conduit – Internal or External
TFTF TDMTDM
Try to be Prepared
• Sweep the T/L you have and make sure it can be used
• At the same time sweep the antenna to check bandwidth
• Think about your back up plan to stay on the air
– Low power filters can be retuned
– Broadband panels as Aux antennas
• Call Manufactures for existing equipment data