1 campus cable tv signal leakage: what’s the story, and what should we be doing about it?
TRANSCRIPT
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Campus Cable TV Signal Leakage:Campus Cable TV Signal Leakage:
What’s The Story,
and What Should We Be Doing About It?
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Disclaimer:Disclaimer:
The opinions expressed by the presenter during this presentation do not necessarily reflect those of The Georgia Institute of Technology, Campus Televideo,
The Association of Higher Education Campus Television Administrators, or the Peabody Hotel.
(But they should.)
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Signal Leakage: TypesSignal Leakage: Types
• Don’t use the “R” word. (Radiation)• Ingress:
Unwanted RF signals getting INTO the Cable System.
• Egress:
Unwanted RF signals getting OUT of the Cable System.
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Signal Ingress:Signal Ingress:
• RF signals outside the cable at or near the same frequency of the RF signals on the cable will cause problems with the RF signals on the cable if they can get in.
Analog Digital
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Cable TV Shares the Spectrum With Off-AirCable TV Shares the Spectrum With Off-Air
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Signal Egress:Signal Egress:
Channels 95 through 22 added in the 1970’s
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Signal Egress: Air Distress Frequency (121.5 MHz)
Signal Egress: Air Distress Frequency (121.5 MHz)
1984 FCC begins Signal Leakage Monitoring Requirements for Franchised Cable TV Systems
Frequency offsets added in 1989.
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Signal Leakage: (CLI) Cumulative Leakage IndexSignal Leakage: (CLI) Cumulative Leakage Index
FCC begins CLI in the 1990’s.
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
What does this have to do with Me?
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
(MVPD=Multichannel Video Programming Distributor)
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
So what does this mean?
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
CFR 47 Part 76, 76.605(a)(12), 76.610-76.614, 76.616, 76.617, 76.1706, 76.1803, 76.1804
Prior to the use of signals in the aeronautical radio bands, and at least once each calendar year,
CATV systems, MVPDs, and Non-Cable MVPDs
must comply with FCC requirements for signal egress.
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Aeronautical FrequenciesAeronautical Frequencies
108 MHz 137 MHz
225 MHz 400 MHz
Channels 98, 99, 14, 15, & 16
Channels 24 thru 53
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Aeronautical FrequenciesAeronautical Frequencies
• CFR 47 76.616 (b)…”The transmission of digital signals in this range is limited to power levels measured using a root-means-square detector of less than 10-5 watts (+34 dBmV) in any 30 kHz bandwidth over any 2.5 millisecond interval.”
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
What do I need to do?
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
If you are going to use the aeronautical channels…
Consult with your Legal department.
Get FCC forms 320 & 321 in order.
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
If you are already using the aeronautical channels…
Consult with your Legal department.
Get FCC forms 320 & 321 in order.
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
• Acquire Commercial Signal Leakage detection equipment.
(Make a “calibrated leak”.)• FM Radio• Contracted Fly-Over
or Ride-Out
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Signal Leakage: Cumulative Leakage IndexSignal Leakage: Cumulative Leakage Index
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Calculating CLICalculating CLI
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Calculating CLICalculating CLI
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Egress:Egress:
Where does Egress come from?
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Signal Leakage: Egress:How does it get out?
Signal Leakage: Egress:How does it get out?
• A lack of proper System Maintenance.
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Signal Leakage: Egress:How does it get out?
Signal Leakage: Egress:How does it get out?
• Loose or improperly made connectors.
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Signal Leakage: Egress:How does it get out?
Signal Leakage: Egress:How does it get out?
Cracks in the Cable Shield.
• How old is your mainline coax? (Coax older than 15 years is very prone to shield defects.)
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Signal Leakage: Egress:How does it get out?
Signal Leakage: Egress:How does it get out?
Attempted signal theft.
Roughly 75% of all cable signal leakage occurs between the Tap and the Television.
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In case you’re Wondering…..In case you’re Wondering…..
“What if I don’t comply?”
(aka: “I’ll take my chances.”)
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Reminder…Reminder…
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Q & AQ & A
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PenaltiesPenalties
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The Bottom Line…The Bottom Line…
File it. (FCC Form 321)
Find it.
Fix it.
Report it.(FCC Form 320)
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Questions?