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![]() " wrote: On Sun, 12 Feb 2012 13:54:36 -0800, Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: ? Joerg wrote: ?? http://www.cablefax.com/ct/sections/...ier_44237.html ?? ?? Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." ?? ?? then ?? ?? Quote "The maximum cable distance supported between the root and the ?? last outlet is 300 feet, with a maximum attenuation of 25 dB". And this ?? is for MoCA, not just cable TV. ? ? ? MoCA is home networking, hence the 300 foot figure. A drop at +10 ? dBmv already allows a 25 dB loss for the cable modem, since they are ? designed to work to -15 dBmv. That webpage also mentions verifing that a ? "drop amplifier does not block Moca". In other words, it's home ? networking for multimedia devices and has nothing to do with the length ? of the cable drop. It is to allow customers to stream audio and video ? within their home, and use services like Netflix ? Hulu on their TV ? sets. ? It is the modern cable TV, like it or not. Sigh. You never back down, even when you are shown that you are wrong. Because I am not. http://publicservice.vermont.gov/con...rts_cable.html Quote "If its under 300 feet, its free to the consumer". Yes, it is as simple as that. You are within 300ft and the cable company must serve you. This is state-of-the-art. Now you'll probably declare the whole State of Vermont to be wrong? The whole state? Na, there's probably three sane people left. The FCC says the requirement is 100 feet in CFR 47-46.606, section three, quoted below: --- (3) The visual signal level, across a terminating impedance which correctly matches the internal impedance of the cable system as viewed from the subscriber terminal, shall not be less than 1 millivolt across an internal impedance of 75 ohms (0 dBmV). Additionally, as measured at the end of a 30 meter (100 foot) cable drop that is connected to the subscriber tap, it shall not be less than 1.41 millivolts across an internal impedance of 75 ohms (+3 dBmV). (At other impedance values, the minimum visual signal level, as viewed from the subscriber terminal, shall be the square root of 0.0133 (Z) millivolts and, as measured at the end of a 30 meter (100 foot) cable drop that is connected to the subscriber tap, shall be 2 times the square root of 0.00662(Z) millivolts, where Z is the appropriate impedance value.) --- That mess in Vermont involves Adelphia cable, and the settlement of a huge fraud lawsuit. They agreed to build to a minimum of 14 homes per mile, when the industry usually stops at 35-40 homes per mile as ever paying back the construction costs. Vermont had them by the balls, if they wanted to renew their franchisee. Adelphia is also heavily invested in FIOS. The other franchises I looked at only had a 300 foot limit if it was Fiber to the structure, which doesn't have the roll off and insertion loss of coax. Here is a typical RG6 from Belden: Freq. (MHz) Attenuation (dB/100 ft.) 5 .67 55 1.60 211 2.87 270 3.24 300 3.43 350 3.72 400 4.00 450 4.26 550 4.71 750 5.59 870 6.00 1000 6.54 This shows the loss at 12.78 dB at 450 MHz which would be a very old system. -- You can't have a sense of humor, if you have no sense. |
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