HDTV Coax cabling

[MarkC]

I need to run about 300 feet of coax from my HDTV satellite dish to the receiver. It will need to be buried. It will be a dedicated cable from LNB to cable box. I would like to use standard RG6 60% al shield cable, copper clad steel conductor (cheap) and route it inside thin walled PE tubing. Will this work? Any better way of doing this?

Any help is appreciated,

Mark

[bfalls]

I did a quick search and found the following information in another forum.

"RG-6 has an attenuation at 700 MHz (pretty standard upper limit of the cable spectrum these days) of 5.6 dB per 100 ft. The signal at the tap of a cable TV plant is about 15 dBm. So, at 150 feet of RG6 from the tap, the signal level is about 6.6 dBm (15 dBm - 8.4 dB of attenuation). But, if you throw a splitter in there (to feed 2 TVs), that's another 3.5 dB of attenuation, or 3.1 dBm.

A TV must have at least 0 dBm at the coaxial input to have a good picture. Any lower than that and the picture starts to get grainy. Also, the lower the signal, the more susceptible the TV picture would be to ingress (RF signals leaking onto the cable, resulting in beats (faint diagonal lines appearing on the screen) or ghosting (multiple images).

RG11 has an attenuation of 4.7 dB per 100 ft at 700 MHz. This gives you about another 1 dB less attenuation over the 150-foot run."

[eisforelectronic]

Signal level at the tap from cable plant may be higher or lower than 15dbm depending on plant design.

RG11 is a little harder to find

We typically round loss on RG6 to 6dbm and Rg11 to 4dbm

On a typical TV you may have signal way lower than 0dbm before you see any grain.

If your fittings are done right, barring any actual defects in the materials or system, you shouldn't get any ingress unless you've got some high power transmitters nearby.

A satellite system may be pumping out much higher db levels, typically loss is much less of an issue with Sat systems.

The basic answer to the question is "Yes, it will work". Although I would think long term in regards to your choice of conduit. Stronger and bigger is better, especially over a run that long. Even completely straight, that could be a tough pull.

[MarkC]

Thanks for the information - I will look carefully at the conduit to be used.

[eisforelectronic]

Thanks for the information - I will look carefully at the conduit to be used.

An extra pullstring or two couldn't hurt either.

[pixelthis]

SIX will do fine, but I would think about putting in a wideband video amp for a run
of that lenght.
Best thing of course would be to get your dish closer, the cost of all that PVC pipe
alone will be worth it.:1: