In a cable TV system, the trunk line cable that leads from the headend to a distribution point. Or the cable running between a central office and a distribution point. A distribution cable then leads to the individual subscribers.
Construction | |||
Material | Diameter (mm) | ||
Inner Conductor | CCA-Copper clad aluminum | 3.15 | |
Dielectric | Foam PE | 13.05 | |
First Shield | Solid aluminum tube | 13.72 | |
Jacket | PE | 15.49 | |
Messenger | Galvanized steel | 2.77 | |
Electrical Characteristics | |||
Impedance (Ω) | 75 ± 3 | ||
Capacitance (pF/m) | 52 ± 2 | ||
Velocity of Propagation (%) | 87.0 | ||
Return Loss | |||
5-1000 MHz (dB) | ≥ 22 | ||
Screening Effactiveness | |||
5-1000 MHz (dB) | ≥ 100 | ||
Attenuation (@ 20oC) | |||
Frequency (MHz) |
Max Attenuation (dB/100ft) |
Max Attenuation (dB/100m) |
|
5 | 0.14 | 0.46 | |
55 | 0.47 | 1.54 | |
83 | 0.58 | 1.90 | |
211 | 0.95 | 3.12 | |
250 | 1.03 | 3.38 | |
300 | 1.13 | 3.71 | |
350 | 1.23 | 4.04 | |
400 | 1.32 | 4.33 | |
500 | 1.49 | 4.89 | |
600 | 1.64 | 5.38 | |
750 | 1.85 | 6.07 | |
865 | 2.00 | 6.56 | |
1000 | 2.17 | 7.12 |