[apriest]

Hello everyone! This is my first post on DIY Forums...I only recently discovered all of you and this is amazing.

Anyways - I'm trying to help my mom upgrade her Comcast service to include digital TV, Internet, and Phone. The serviceman said that the quality of the signal running to the cable outlets was very poor. We tried to locate the junction box or split point where the origin line branches out but there doesn't seem to be one. We identified the source line that runs from outside but it seems to run into the attic over the garage and it disappears above the master bedroom. But there is no panel or access to the cable that we can locate. The house is a townhome, relatively newer construction (she's been here for 7 years and is the first to occupy), but I get the feeling that the contractor was less than exemplary.

There are no shared boxes (like in an apt setting). Is it possible that the contractor just split the coaxial cable as he went along and then buried them in the walls??? Ugh.

Thoughts on this? Any solutions that don't involve fishing through the walls? Maybe a signal booster?

Sorry for the lengthy post...and any insight is GREATLY appreciated.

Best.

 

[220/221]

You have one cable going in and several cable openings inside?

If they split inside, they generally do it in the walls behing the cable jacks.

If they did it in an inaccessible attic space or closed in wall cavity, you are screwed and need to run new cable.

Sometimes it's easy, sometimes it aint.

 

[jerryh3]

Take one of the cable plates off and see if they used splitters inside the boxes. Also, what do mean the cable disappears above the bedroom? Does it run down into a wall from there? How many rooms would she like the tv to be in? Where would she like the cable/phone modem?

 

[apriest]

Thanks for the responses! Sorry for any ambiguity. The source cable runs from outside across the garage attic and into the wall behind the master bedroom. I cannot locate any splits before that point so obviously the splits were made in the wall cavities (which makes my life fun).

She wants tv in a loft on the second floor and in the master bedroom on the first floor (which is almost below the loft). The cable/phone modem would ideally be with that upstairs connection in the loft.

Since the issue is low signal quality, is it possible that a short-term fix would be a signal booster/amplifier? At least enough to tide her over until I can tackle the larger project of running new cable in a logical fashion?

Thanks again.

 

[gregzoll]

Not with Digital Cable. If there is poor signal quality, get CC to come in and look at it. They have the tools & testing equipment to determine.

 

[kbsparky]

Digital cable service requires separate lines for each jack. This includes internet modems, and VOIP devices.

 

[williswires]

Your cable modem should get it's signal from the very first splitter. Anything else is a degraded signal and will give you problems/internet connectivity issues.

The incoming cable needs to go to high quality splitter as it comes in the house from Comcast. One output goes to the cable modem, the other output serves the rest of your installation.

 

[jerryh3]

Where are you located?

 

[apriest]

This is all great information. The CC guy is supposed to return today so having this knowledge will be very useful, even if it painting a bleak picture for the work I have cut out for me!

I am located in Northwest Indiana.

 

[J. V.]

You could try an inexpensive amplifier at the TV furthest from the source signal. If it works better you can install them at every point of use, if needed. They run under $25.00 each and need a 120 volt receptacle.

 

[gregzoll]

It can still be daisy chained, and does not require Ethernet or voip if you think that is what it is called. You really need to read about the technology before just posting FUD.

 

[gregzoll]

You cannot use amps with Digital cable.

 

[gregzoll]

A cable modem is only used to connect your computer, and yes it can be placed at the head of the line not 6 split lines down. May still work, but not in the best quality.

 

[InPhase277]

Well, let the other TVs have crappy signal. Go back to the garage attic where you have verified the cable is unspliced, and splice it there. Use the good compression connectors and do a good job. Run a line from there to the spot where you want the modem/phone and new TV.

Better yet, run a new line all the way outside, with no splices.

 

[Scuba_Dave]

When my digital went in they ran a line to the basement
Big old UPS/combined system installed for phone/cabel/Internet
From there to a splitter - 1st line from splitter had to go to the cable modem
Then other lines to each TV, not daisy chained
Since I'm remodeling I'm running new/more Quad 6 runs thru-out the house
Plus phone & CAT6 runs

They should run a new main line to a central location
After that it is your cost of they run more
I had one TV that had poor pircure - it had a splice in the line, older cable
I ran a new line & the picture is much better

 

[jerryh3]

You cannot use amps with Digital cable.

Really? Why not?

 

[theatretch85]

When I went through with my remodel on my house, I ripped out ALL of the old coax and 4 conductor phone wiring, it was all split in different locations and was it bad condition. Instead, I home ran all new quad sheild RG6 coax, Cat 6 data lines and Cat5e phone lines to a server room im in the middle of building. Charter came out and ran a brand new bright orange cable through my backyard to replace the old cable in the ground (which thankfully the install tech didn't see - so he ran the new cable). The old cable was spliced in the ground about a foot from the house.

I uUsed compression fittings everywhere, in fact the charter tech actually handed me a full bag of compression fittings and told me not to buy any. I already had the compression tool and all the RG6 quad sheiled cable I needed (2 partial 1000' boxes) and he we figured out how many cable connections I needed and came up with a splitter configuration that would work and he gave me those too.

Cable and phone modem, and digital HD recievers all need the best possible signal, I think no more than 2 total splitters for these devices (ie main splitter connects to a downstream splitter and these devices must connect no further down than that second splitter). I'll have a cable modem with 20mb internet, phone modem that will both sit in the data rack in the server room (where all the CATV cable run and will be split to the different rooms). Then I will have at least 1 or 2 HD cable boxes, and the rest of the tv's just getting basic cable tv.

Amplifiers can be used on basic cable tv (like the 25 dollar one mentioned earlier here) but they will not work on digitial cable (like for the modem/phone/HD cable box). Digital cable is bi-directional and runs in the 1000-2000mhz (1ghz to 2ghz) range and most amplifiers only operate in the 47-950mhz range (where the basic tv channels reside).

At my parents place (back when I was still living at home) I re-ran all the coax cable, and with the number of connections coming out of the attic at the opposite end of the house I ended up buying a Blounder Toungue Apartment Complex amplifier on ebay to power a 12 port splitter (this was after a couple splitters already in the garage. It worked great for the basic cable to all these tv's (and in some cases TV tuner in a PC) and was pretty cheap for a beefy (I believe 30db) gain.

They of course make bigger and better amplifiers, but to get one for digital cable would be rather expensive. It'd be cheaper to run all new cable even if it meant tearing through walls to run the cable. Cable is cheap, and wall repair isn't all that hard to do; and once its done you shouldn't have to worry about it. The amplifiers can fail overtime or be un-reliable if subject to the right conditions; I think my Blounder Toungue amp no longer works as good as it used to as it sits in the attic so its subject to the high heat in the summer and extreme cold in the winter.

Dang this post went on a lot longer than I intended it to.....

 

[jerryh3]

When I went through with my remodel on my house, I ripped out ALL of the old coax and 4 conductor phone wiring, it was all split in different locations and was it bad condition. Instead, I home ran all new quad sheild RG6 coax, Cat 6 data lines and Cat5e phone lines to a server room im in the middle of building. Charter came out and ran a brand new bright orange cable through my backyard to replace the old cable in the ground (which thankfully the install tech didn't see - so he ran the new cable). The old cable was spliced in the ground about a foot from the house.

I uUsed compression fittings everywhere, in fact the charter tech actually handed me a full bag of compression fittings and told me not to buy any. I already had the compression tool and all the RG6 quad sheiled cable I needed (2 partial 1000' boxes) and he we figured out how many cable connections I needed and came up with a splitter configuration that would work and he gave me those too.

Cable and phone modem, and digital HD recievers all need the best possible signal, I think no more than 2 total splitters for these devices (ie main splitter connects to a downstream splitter and these devices must connect no further down than that second splitter). I'll have a cable modem with 20mb internet, phone modem that will both sit in the data rack in the server room (where all the CATV cable run and will be split to the different rooms). Then I will have at least 1 or 2 HD cable boxes, and the rest of the tv's just getting basic cable tv.

Amplifiers can be used on basic cable tv (like the 25 dollar one mentioned earlier here) but they will not work on digitial cable (like for the modem/phone/HD cable box). Digital cable is bi-directional and runs in the 1000-2000mhz (1ghz to 2ghz) range and most amplifiers only operate in the 47-950mhz range (where the basic tv channels reside).

At my parents place (back when I was still living at home) I re-ran all the coax cable, and with the number of connections coming out of the attic at the opposite end of the house I ended up buying a Blounder Toungue Apartment Complex amplifier on ebay to power a 12 port splitter (this was after a couple splitters already in the garage. It worked great for the basic cable to all these tv's (and in some cases TV tuner in a PC) and was pretty cheap for a beefy (I believe 30db) gain.

They of course make bigger and better amplifiers, but to get one for digital cable would be rather expensive. It'd be cheaper to run all new cable even if it meant tearing through walls to run the cable. Cable is cheap, and wall repair isn't all that hard to do; and once its done you shouldn't have to worry about it. The amplifiers can fail overtime or be un-reliable if subject to the right conditions; I think my Blounder Toungue amp no longer works as good as it used to as it sits in the attic so its subject to the high heat in the summer and extreme cold in the winter.

Dang this post went on a lot longer than I intended it to.....

Can you tell me where you're getting your information for the cable frequencies? I haven't seen any digital cable boxes/cable modems that run over 1GHz. Maybe a Satellite system, but not CATV.

 

[williswires]

Here's the amplifier I use. Works great with digital and HDTV, and allows the comm paths back to the service provider for on-demand and pay-per-view commands. Online at $190.00

(I don't use the IR features...)

http://www.linearcorp.com/product_detail.php?productId=190

The description:

The Model DA-550BID Bi-directional RF Distribution Amplifier with 12-volt IR is the heart of a multi-room distribution system with outputs to eight televisions with coax runs up to 150 feet. The Model DA-550BID has three inputs, one from CATV and two from ChannelPlus 5400, 5500, or SVM series modulators. The Model DA-550BID can handle an extremely wide range of input signals from NTSC and digital TV. The Model DA-550BID offers a 5-42 MHz bandwidth return path for bi-directional communication for use with digital cable interactive set-top boxes.
The Model DA-550BID can be powered locally with its included power supply or remotely from up to 75 feet away by using an in-wall power injector wall plate Model 2010 or any 5500 series or SVM series modulator.
The Model DA-550BID offers optional IR control of connected video sources and whole house IR integration with a built-in 12-volt IR engine. Adding a Model 2100A wall plate and a 12-volt IR target to the coax run of any room allows IR signals to be routed to either a Model 2010 wall plate, 5500 series, or SVM series modulator.
Features

• 54 MHz to 1 GHz forward bandwidth
• 5 MHz to 42 MHz reverse bandwidth
• 3 dB nominal gain on TV outputs
• Maximum input level 20 dBmv
• Can be used in locations without electrical access and powered remotely with a ChannelPlus modulator or the Model 2010 wall plate
• 6.5" W x 1.25" H x 4.5" D

 

[gregzoll]

Because it degrades the signal even further, and will not do anything to improve an already crappy signal from the provider. As for the amp that williswires posted, it is only for Digital TV when you are trying to improve the quality of Over The Air. Analog Cable, which is quickly going away so that providers can encrypt the signal of their service & provide over a 100% digital system, which this amp also helps only if the signal is Analog, not Digital.