(10-05-2013 02:56 PM)TigerBill Wrote: So we moved the other day, only to discover that, while the previous owner's had Comcast internet and cable, we couldn't have it because our house is more than 300 feet from the box. A relay has to be installed. The signal strength was fine, the previous owner had no issues, but this is 'policy.' So who knows when they will get around to doing the work, and in the meantime it's finding a hotspot (in Oakland!) and over the air TV.
Talk about living primitive!
Of course it might be you will need to consider just using AT&T for internet and video service. If you don't want to pay for regular phone service, request "no ring phone service" for minimal charge as compared to regular phone service.
If the cable is already installed then a line amp is all that is needed as I am sure your are aware. A relay would be for the return signal to Comcast. This link shows the signal amplifier is that is needed if the signal has dropped below acceptable levels in most cases. You would either need a forward gain or a by-pass gain amp.
http://www.parts-express.com/pe/showdetl...er=182-570
*Forward gain cable amplifiers can by used in a variety of different situations, from compensating for lower signal strength from your cable provider, raising the strength of the signal from your cable provider, or increasing the signal before multiple line are connected. The forward gain amplifier works in providing an increased signal level into your home on the upstream band of 54-1000 MHz, and still allowing the 5-42MHz return band to be passed on back to the cable provider with little or no loss in signal level. Things to look for when purchasing a forward gain amplifier are, Low noise of 3 dB or lower, low distortion and excellent return loss which should be about 20 dB.
*Bypass cable amplifiers work in the same way as forward gain amplifiers to increase the signal level on the 54-1000 MHz band for high speed internet, interactive television and telephony services, and still allowing the 5-42MHz return band to be passed on back to the cable provider with little or no loss in signal level. The difference from the forward gain amplifier is that the bypass amplifier has a built in relay switch designed to bypass the amplification circuitry to bypass mode and provide constant uninterrupted telephony service in the event of a power outage.
Look at the incoming cable and check to see if it is RG-6 quad shielded. If it is RG-59 it is not really capable of handling the bandwidth for high speed internet or HDTV when the cable has to be that long from the pole/box. *Any RG-59 inside the house would also need to be upgraded to RG-6 quad shield.
When it is that long of a run from the pole/box it could require RG-11 quad shield. Much thicker cable as well as more expensive.
Usually used in commercial installations and office buildings where utmost signal quality is demanded, or for very long runs.
I bet when the cable was installed in the home that they overlooked the distance and depending when it was installed it very well could be RG-59 regular cable, not even quad shielded. Probably copper coated steel center conductor also, not all copper. Cheapest crap available.
That is what most used from the pole to the house.
I assume the area distribution feed on the pole is fiber optic. With that I bet Comcast would now want to install RG-6 quad shield or maybe even RG-11 quad shield since the run is over a 300 foot run. For that they would nail you because they probably have to special order RG-11.
Coax Cable Signal (Attenuation) Loss per 100ft. Sorry but the alignment of the numbers won't space right when I hit post, but you can go to this link if you need more cable,internet/video info.
http://www.dslreports.com/faq/cabletech?text=1
RG-59 RG-6 RG-11
1MHz 0.4dB 0.2dB 0.2dB
10MHz 1.4dB 0.6dB 0.4dB
50MHz 3.3dB 1.4dB 1.0dB
100MHz 4.9dB 2.0dB 1.6dB
200MHz 7.3dB 2.8dB 2.3 dB
400MHz 11.2dB 4.3dB 3.5dB
700MHz 16.9dB 5.6dB 4.7dB
900MHz 20.1dB 6.0dB 5.4dB
1000MHZ 21.5dB 6.1dB 5.6dB