1. Texas Gulf Coast Chapter of SCTE presents…
“Cumulative Leakage Index”
What? Why? Who? Where? When? And How?

2. Listen for answers to these questions…
What is CLI?
Why do I need to be concerned with CLI? 
FCC ---who are they and why are they involved? 
Why keep leakage logs?
What’s a microvolt? 
What is noise and how can it impact customers? 
Is there a direct correlation between CLI and other distortions?
Why is the customer's home a major contributor to system problems? 
Why is proper cable and connector craftsmanship so important?

3. What is Leakage?
*Cumulative Leakage Index (CLI)
CLI is the net effect of the combination of all the leaks in the system added together =the amount of radio frequency (RF) signal that escapes or infects the cable system
These cumulative leaks form an invisible cloud of unwanted RF energy over the cable system
Leakage results from:
Improper cable installation
component corrosion
poor product design
Vandalism
cable breaks
poor connections

4. Two types of leakage: Egress and Ingress
Egress= RF signal leaking out of the cable system
Damaged cable
Improperly installed cable
Signal escapes and follows the path of least resistance including free space (air), strand, power and phone lines
Ingress= RF noise or interference that leaks into the cable system through a break or external leak (loose connectors)
Hair dryers, microwaves, radios, etc.
Feeds into the coax drop from bad TV’s, long center conductors, amplifiers, jumpers, customer equipment (VCR)

5. Ingress/Egress Ingress: RF signal leaking into the coaxial plant
RF signal leaking out of the coaxial plant

6. Why Is It Important to Determine Leakage?
Cable television systems and licensed over-the-air broadcasters use many of the same frequencies to transmit programming. Specifically, cable systems use TV, radio and aeronautical radio channels, among others, within their cable plant.
Cable operators are considered the secondary users of these frequencies; therefore they must not interfere with the licensed over-the-air users who are the protected (primary) users of these frequencies.

7. What Problems Can Signal Leakage Cause?
Cable signal leakage can interfere with any of the over-the-air services that happen to be using the same frequencies as the cable operator and that are within the vicinity of the cable system.
Such interference, especially on the emergency channels, can interfere with the communications of safety personnel or airplane pilots.
When such interference occurs, it can endanger the lives or hamper the rescue efforts of safety personnel.

8. What are the FCC Rules Governing Signal Leakage?
The FCC (Federal Communication Commission)has set maximum individual signal leakage levels for cable systems.
The FCC sets even more stringent limits for cable systems that may interfere with aeronautical and navigation communications.
As a further measure, the FCC requires cable operators to have a periodic, on-going program to inspect, locate and repair leaks on their systems. –FCC files include:
CLI quarterly ride outs (100% of system & log all leaks)
Annual Flyovers (report on form 320)
Daily Leakage Logs (date found/date repaired)

9. Can the Cable Company be penalized if it fails to control CLI?
4/17/2012
Pays to keep the system clean…
In this Notice of Apparent Liability for Forfeiture (NAL), we find that Cebridge Acquisition, LP (Cebridge), operator of the cable television system in Honey Grove, Texas, apparently willfully violated Sections (a)(12) and (a)(1) of the Commission’s rules (Rules),[1] by failing to prevent excessive signal leakage in the Honey Grove cable system.  We conclude that Cebridge is apparently liable for a forfeiture in the amount of eight thousand dollars ($8,000). 

10. Quarterly CLI Drive Out Results
Unauthorized Connection %
Loose F Connector %
Loose Terminator %
Replace Connector %
No Fault Found %

11. Who’s Responsible? And What can I do?
It is a shared responsibility across Operations and Engineering.

12. Five Steps in Leakage Abatement
Detection
Location
Measurement
Correction
Re-measurement

13. Detection (What do I need?)
Carrier Generator- a unique frequency inserted by the headend that can be recognized by the leakage detector tuned to the carrier’s frequency
Leakage Detector- (Seekers’, Searchers’, Sleuths’)-provided and used by all technicians to detect leaks in the free space where RF energy is encountered

14. Calibrating Leakage Equipment
1.Connect calibrated signal source set at 20 uV/m.
2. Position the dipole antenna.
3. Adjust to read 20 uV/m.

15. Identify the precise Location of the leak with your Leakage Detector

16. Hand Held Detectors
Check the battery voltage, insure the unit is charged before you proceed to isolate the leak
Listen to the audible alarm indicator as you proceed to isolate the leak source
Increases in the tone pitch indicate you are closer to the source
Decreases in the tone pitch indicate you are moving away from the leak source
Follow the manufacturers recommended mode to identify the leak source
Once the leak is identified to a pole, cable, or a home, follow standard troubleshooting procedures until the leak is within compliance

17. Measurement-rules of engagement
Once a leak is located it must be measured
μV/M What is a microvolt per Meter?
Standard unit of measure for CLI
50 Ohm off air measurement
Voltage developed in 1 meter of infinitely thin section of wire submerged in a leakage field produces 1μV of energy
All leaks greater than 20 microvolt's MUST be repaired per FCC rules
Any leak greater than 50 microvolt's MUST be repaired IMMEDIATELY per FCC rules

18. Measurement-rules of engagement (cont.)
Only leaks above 50 μV/m are used in CLI calculation
All measurements taken outside MHz must be converted as if they were taken within the band
Leakage Detector-measures the level of the leak
Take the reading at about 10 feet (3 meters)
Repair it
Re-measure

19. Measurement-rules of engagement (cont.)
Use a calibrated halfwave dipole antenna
Antenna must be elevated 3 meters off the ground and positioned 3 meters from the leakage source
Antenna must be rotated 360º in the horizontal plane for maximum reading

20. Let’s Practice finding a leak
Turn on your Leakage Detector!

21. Measurement-Why do we care?
1. Meet FCC Compliance
2. Prevent Off-Air Interference
Aeronautical & Aircraft Communications
Amateur Communications
Broadcast TV signals (Analog & Digital)
Public and Emergency Communications
Radio Mobile Communications

22. Measurement-Why do we care?
3. Improves System Performance
Reduces Repeat Service Calls
Locate Physical problems

23. Correction of Leak
80% of all leakage is caused by problems from the tap to customer equipment
Common Causes of Leakage-
Loose drop connectors
Improperly installed connectors
Inferior quality coaxial cable, passives, or connectors
Poorly-shielded drop cables
Bad connectors at the taps
Bad/loose port terminators
Corroded connectors

24. Correction Common Causes of Leakage-cont.
Cracks in the trunk and feeder cables
Animal chews
Physical trauma to cables or connectors
Aging and environmental stress
Loose hard line connectors

25. Correction Common Causes of Leakage-cont. Customer installed equipment
Damaged amplifier housings
Loose amplifier housing lids
Broken tap ports
Poor installation of splices and connectors
Poorly-shielded customer premise equipment

26. Ingress impacts on Digital Channels
Macro Blocking (Tiling)
Freeze Frame
Picture and Sound go to black
Robotic Voice
Data Packet Loss or slower speeds
Repeat Service Calls

27. Ingress impacts on Analog Channels
Lines in picture
Ghosting
Pay-per-view problems
Interference with two-way radio services using the same frequencies
Repeat Service Calls

28. Correction
Repair the leak- determine the root cause and use TWC procedures to implement proper restoration
Tighten or replace connectors
Replace cracked or damaged cable
Terminate open ports with 75 ohm terminators
Correct customer created issues (replace splitters, self-run inferior cable)
Properly terminate unauthorized connections and report theft of service to Audit/Security operations

29. Audit/Security Process
Insert your local process and contact information

30. Re-measurement
Take a final reading using the same equipment and record the corrected CLI calculation (reportable to the FCC)
If the leak is still above 20 microvolt's it is NOT repaired (incomplete diagnosis-reengage)
Work the issue backtracking all the cable and connections
Correct issue until leak is under 20 microvolt's

31. CLI tips Turn on your CLI equipment and use properly
Record/Repair/Re-measure your leaks
Tighten all connectors
Use PPC Signal Tight Connectors indoors
Properly terminate open ports
Disconnect unauthorized drops and properly terminate

32. Signal Tight Connectors help prevent ingress/egress

33. Benefits of CLI program
Reduced ingress/noise in the plant (SNR)
Increased plant performance (FEC)
Better CPE performance thus improved Whole House Check
Reduction in Trouble Calls (TC to RGU and rework)
Customer Satisfaction!

34. Customer FAQ’s Be careful using the word “radiate.”
(Q & A’s from the FCC website)

35. FAQ’s from the customer
Does a Cable Operator Need to Come into My Home to Monitor for Signal Leakage?
Usually, no. Cable operators can use equipment to locate the general area of a leak. To pinpoint a leakage source for subsequent repair, however, the cable operator may request access to your home.
Am I Required to Let the Cable Operator into My Home to Monitor for and Repair Signal Leakage?
Homeowners have the right to deny access to their premises. If a leak cannot be repaired without access to your home, however, a cable operator can disconnect your service for denied access.

36. FAQ’s from the customer (cont.)
Can My Cable Operator Terminate My Service Because of Signal Leakage?
The FCC’s rules allow cable operators to disconnect service in order to repair signal leakage that exceeds FCC standards. The operator restores service when the signal leakage problem is remedied, and may not charge you for service while it is disconnected.
Is the Cable Operator Responsible for Repairing Signal Leakage on Subscriber-owned Equipment?
No.

37. FAQ’s from the customer (cont.)
Can I Hook Up a Second Set Myself?
In terms of the signal leakage rules, yes, but because the cable operator is responsible for leakage from the wiring, the operator can either refuse to connect to it or terminate service if the hook up causes signal leakage problems.
Is Signal Leakage Biologically Harmful?
The power levels used in a cable system are low. Therefore, it is unlikely that cable signal leakage from a cable facility will exceed the FCC’s RF allowable limits for RF exposure.

38. Thanks for your Participation
Join the SCTE Texas Gulf Coast Chapter
TODAY!!!