Cable TV cable type question.

[Rupp]

My cable TV feed comes to my house as RG-6. It then currently connects to a 1 - 6 splitter on the side of the house and the 6 "legs" are RG-59. I'm starting the installation of a wiring closet and was wonder if I could use and existing piece of RG-59 from the attic as my "supply" line or should I attempt to route (would be very very hard) RG-6 from the cable supply line to the new wiring closet.

[Stevech]

Rupp
do you have an amplifier ahead of the 6 way splitter? If not, I'd suggest you do so. That's a lot of attenuation per port.

If you have an amplified signa, RG59 is marginally OK. It is quite lossy at the higher channels - it tends to unbalance - without an amp, you might get noisy pix on the high channels.

also - if you have a cable modem, there are other considerations.

[anogee]

I just rewired mine, but don't have the luxury of a wiring closet. Instead, I increased the size of the cable wiring box on the side of my house. If you have a cable modem, I recommend that you keep the tap the cable company gives you for that, then go to a high quality 20 - 25dB amp, then a splitter. It works fantastic for me. I'm using the Leviton 2-Way 2 GHz amp, and all TVs look great. For a few I'm forced to use an additional 2-way or 3-way behind the TV. (For VCR, DVD recorder, etc.) Still has a great signal after this additional split.

What I learned: Put your amp AFTER the cable modem tap (even with a 2-way amp, this is the best way to go), buy the best amp you can afford, and don't over-amplify. You shouldn't amplify from start to end more than 3 - 6 dB after the amps, splitter, etc.

[Rick Tinker]

Rupp,

I would recommend the new wire - if it were RG6 already you can live without going to RG11, but RG59 is not going to be that good for broadband Internet and today's huge channel lineup CATV.

Do it like in the old days - run it outside along the wall of the house!

[Rupp]

Rick,
I thought abut running it up the wall and into the soffit. I think I will do it right and connect it to the incoming cable from the cable company and run it under my crawl space and then up to the attic. So 2 new questions. What is RG11? I thought the new stuff was RG6. Also what should I use to make the connection to the cable company? Just a simple cable to cable junction "piece"?

[Stevech]

I vote for putting the amp on the main incoming line, then a 2 way splitter, one to the cable modem and the other to feed splitters to all TVs. this keeps the cable modem input (downstream) high. Use a downstream amp with a return path for your cable modem.

I also use a reverse amp for my cable modem. To boost the return signal. Because there's a too-long coax from my house to the cable company's demarc. My cable modem was running max power upstream.

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[Rupp]

stevech,
Why in the world would I need all of these upstream amps and downstreama amps? My cable modem is lightning fast as it is. What do these amps by me?

[Stevech]

In my case, the cable modem's signal, especially the upstream, was intermittently very unreliable. Due to a long lossy coax from my home to the demarc, which I could not replace. Intermittent weak signals - varies by time of day and weather, and the upstream is low freq in cable - like 40Mhz, and thus subject to all kinds of interference ingested onto the cable. But if you are luck, you'll have 24/7 reliable operation. Weak signal = higher error rate (with retries).

The downstream amp - any house with more than a 4 way splitter might oughta have one - because each port on a splitter is 3dB of loss - half power. A 6 port splitter, or combinations of 2-way totalling 6 or more, attenuate the signal. Most cable companies don't deliver enough excess signal to assure a low-noise (snow-free) signal - especially on the high channels - after that many splitter ports.

[Rupp]

Ok, That was a good explanation. When I get to this point I'm sure I will have dozens of questions. Thanks to everyone for the Video 101 lesson.

[JLehnert]

RG11 is a specialized 75 ohm coax for satellite feeds. Usable, but in your case, I would go with RG6QS (Quad shield).

[anogee]

I have seen much debate on the connection hookup of amps, cable modems and TV's. I think the answer depends upon your case, but I can tell you that cable companies often use taps and not splitters. A tap is like a splitter, but it routes more signal to one side than the other. "Typically" and for my home, the cable comes into a tap, with a -6 dB side going to the cable modem, and the full strength passthrough side going to my TVs in my house. They do this so your home TVs experience almost no lose of signal from he tap, and the cable modem, while loosing 6 dB, still works fine because the headend was designed for that 6 dB lose. The LAST thing you want to do is disturb the signal to the cable modem, UP or DOWN.

My advice here, is that if your cable modem is not working with the standard configuration that the cable company gave you, call them and let them fix it. They can crank up the data feed signal or give you an amp, but it shouldn't cost you anything.

Now, once past the tap, I added an amp because I have a whole lot of TVs, and the amp simply compensates for the splitter. From what I heard, most cable companies will also fix low TV signals for you as well, for free, but in this case I thought it better to just add my own amp.

[Stevech]

I had to use the amps because the cable company says "the coax from the cable co. demarc to your condo is not the cable company's problem. Tough luck" And, I'm stuck since the faulty 100' of cheap-o coax runs through the attic of other condos to get to me, not replaceable. And the condo association is less than sympathetic.