188
FCC Rules
Cumulative Leakage Index - continued
The following formula may be substituted to determine the CLI
figure of merit. Compliance is attained if the formula yields a figure
of merit less than or equal to 64.
Example: Given the following information about a cable sys-
tem, determine the CLI.
Mp = Total plant miles = 1500 miles
Md = Plant miles driven = 1350 miles
Number of leaks and level of each in µV/m =
n1 = 300 leaks @ L1 = 50 µV/m
n2 = 30 leaks @ L2 = 100 µV/m
n3 = 3 leaks @ L3 = 450 µV/m
Sum of:
niLi2 +
n2L22 +
n3L32 =
(300 x 50 x 50) + (30 x 100 x 100) + (3 x 450 x 450) =
607500 =
1657500
CLI =
10 log (1.11 x 1657500)
=
10 log (1839825)
=
62.65 ≤ 64
where:
Mp = Total Plant Miles (miles)
Md = Total Plant Miles Driven (miles)
n
= Number of leaks with the same level
L
= Level of the leak in microvolts per meter (µV/m)
k
= Number of different levels
Summary of Contents for AMM-806
Page 86: ...79 TVCB PC Installation ...
Page 93: ...86 SMI Installation Torque Patterns 1 Start Here 2 3 4 5 6 1 Start Here 2 3 4 4 PORT 8 PORT ...
Page 125: ...118 Fiber Optics Fiber Loss vs Path Length Single Mode 1550 nm ...
Page 156: ...149 Cable TV Channel Format NTSC NTSC Composite Video Waveform ...
Page 157: ...150 US Frequency Spectrum ...
Page 158: ...151 FCC Aeronautical Band Frequencies Used for Communication and Navigation ...
Page 175: ...168 Common CATV Symbols ...
Page 176: ...169 Common CATV Symbols ...
Page 177: ...170 Digital L Band Distribution Symbols ...
Page 178: ...171 Digital L Band Distribution Symbols ...
Page 183: ...176 Typical Cable Attenuation Chart in dB 100 Feet 68 F 20 C ...
Page 187: ...180 Echo Rating Graph ...
Page 188: ...181 Signal to Interference Limits Non Coherent Carriers ...
Page 190: ...183 Heterodyne Modulator Analog ...
Page 191: ...184 Heterodyne Processor Analog ...
Page 213: ...206 Multiplexers ...
Page 285: ...Rev 8 0 ...