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splitter after grounding block?

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toyz72

Occasional Visitor
i live in a two story home and for some reason they never ran a cable line to my office.my office is located on the first floor.its pretty much impossible to run a cable line from the upstairs to the office.

my question is....can i run a splitter after the grounding block on the outside of the house?it would be much easier to run a line from there. this would be for internet.

i use comcast cable 60 down/12 up. i dont think signal strength is an issue.but im not sure what else i might need to run a new line?
 
To eliminate unnecessary terminations and devices just replace the grounding block with a two way splitter. Splitters have a terminal to connect to your grounding point.

If you have the skills and tools replace the existing f- fittings on the exterior of the house as part of this project to be sure you have excellent connections.

Also be sure that you have drip loops on all the wires connecting to your exterior splitter/ground block to keep water away from the connections.
 
i hope this is what you need? can you give a link to a good splitter with ground?
 

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i hope this is what you need? can you give a link to a good splitter with ground?

Your downstream can handle a -3.5 split but your upstream might be an issue. Adding -3.5 split will cause your upstream to hit around 50 dbmv witch is max you want to take it you could give it a try and see. Here is the propper splitter that comcast uses and is what you will need.

http://www.amazon.com/dp/B007YV0UQW/?tag=snbforums-20
 
i hope this is what you need? can you give a link to a good splitter with ground?
As far as I know all splitters have the screw for attaching a ground wire.

If you go to Amazon and search for 2 - Way Splitters you will get hundreds of hits. Since you didn't say anything about using MOCA, most any splitter that passes 5 - 1000 Mhz will do.

Cheaper option is to catch a Comcast installer on the street or at their nearest service facility and nicely ask them for a splitter. They probably have hundreds of them on their truck and unless they are a real prune they will give you one. A contract installer might be different as they might have to provide their own materials.
 
I would stick with the splitter i posted in the link above its the same as comcast uses and is of high quality. Some splitters look nice with gold plating and such but they are considered junk and should be avoided.

Around here if comcast even sees splitters other then what they use they will replace it. Also good idea about flagging down a comcast tech i am sure they would just give you one with no issues thats how i got my cable simulators i needed because my downstream power was to high.
 
thx for the answers everyone. i guess the next question should be what line to use? i was thinking rg6 direct burial? the new line would be less than 50 feet.
 
thx for the answers everyone. i guess the next question should be what line to use? i was thinking rg6 direct burial? the new line would be less than 50 feet.

Do you have to bury the line ? If so i would go with RG6 quad shield direct burial. If not then RG6 standard would be fine for runs under 100 ft. Also as stated earlier once you split the line your going to raise your upstream level by +3.5 dbmv if you start hitting the 50 dbmv area you wont have any wiggle room if temps get hot outside it may put you over the edge and problems could result. Just a FYI.
 
I put RG6 underground - just a deep slit in the sod, using a flat blade shovel (no curve). And soaked the sod prior day.
Twice a year, the gardeners run a sod aerator machine (beast) which goes down about 3-4 inches.
The cable survived the first one!

On cable modem readings: esp. upstream. When looking at the upstream numbers, you cannot just look at what's displayed. That's the power leaving the modem. It is attenuated according to the number of splitters between the modem and the cable co. demarcation (interconnect, curbside, etc.). And if you have a coax amplifier that has a return amplifier as well as downstream amp, then that is additive.

Example: Cable modem web page says upstream at this moment in time, is +35dBmV. There are splitters totalling 9dB (mind the n-way splitters, per port loss), and there's an amp with return gain of 10dB. So the power leaving your home would be +35 - 9 + 10 = 36dBmV. If the cable amp has no return amp, it would be +35-9 = 26dBmV leaving the house (i.e., at the demarcation). So in this latter case, the missing 10dB benefit from the amplifier should cause the cable co. head end to adjust power upwards by that 10dB, and the modem web display would be +45.

Hope this is clear. The average cable tech. doesn't know the above. They look for something like 45dBmV and don't take into account the splitter losses and upstream amp gain (if any).

Ideally, the wiring is always such that the cable modem (and digital phone) get the first -3.5dB down and there are not lots of splitters before the modem. At my house, the cable from my home ran 150 ft. through 25 year old RG59, and that was damaged somewhere we couldn't find, hence the need for the return amp.

The upstream is in the 40MHz area, so the coax losses are nill, compared to the downstream's high frequencies.

Lastly, the set top box for cable TV has an upstream just like the cable modem, though it is narrower in bandwidth. There's a way to see the signal strengths at the set top box. For mine, you hold down the OK key on the remote for like 15 seconds.
 
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[QUOTE="Kal-EL, post: 190644, member: 22229" Also as stated earlier once you split the line your going to raise your upstream level by +3.5 dbmv if you start hitting the 50 dbmv area you wont have any wiggle room if temps get hot outside it may put you over the edge and problems could result. Just a FYI.[/QUOTE]

I would not worry about the 3.5 dbmv signal loss. If you have both TV and HSD data you are always going to have a splitter so at least having a single splitter is almost always SOP.

FYI the splitters I have from Comcast Chinese and branded Regal. I'm sure Comcast buys splitters by the millions and price is the deciding factor if the splitter meets minimum engineering standards.

At least as important as the signal loss from splitters is bad or loose connections and water ingress into the cable.
 
At least as important as the signal loss from splitters is bad or loose connections and water ingress into the cable.

Agree but also in some areas the signals are not balanced well. That said his upstream power is already at 47 dbmv on one channel adding a splitter will raise this to 50.5 dbmv just barely in spec at 51-52 problems can and will start. Just saying i deal with this all the time and just dont want to see the op start having slow downs and random modem reboots.
 
On cable modem readings: esp. upstream. When looking at the upstream numbers, you cannot just look at what's displayed. That's the power leaving the modem. It is attenuated according to the number of splitters between the modem and the cable co. demarcation (interconnect, curbside, etc.). And if you have a coax amplifier that has a return amplifier as well as downstream amp, then that is additive.

As i understand this thread the OP does not have any splitters or amps in the line just a straight run from the tap to the grounding block and to the modem. So indeed he could run into upstream signal issues adding 3.5 Dbmv attenuation to the line. I have read boat loads of posts on other forums and under docsis 3 standards 50 dbmv is about the highest you can get away with before issue start to crop up.
 
ok guys...im really trying to keep up with all this. maybe i should explain better. my cable line comes in at ground level,then go's clear up to the attic,then down to the e panel on the second floor. from there it splits of to 3-5 different rooms....from on big splitter.

all i want is a simple line to my office. the easiest way would be to split it off at the cable block and run a 50 foot line under ground to the office.

i thought maybe my internet would have been stronger on one split and a 50 foot line?but i'm a super noob compared to you guys.
 
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While we debate how many angels can dance on the head of a pin do the following:
1. Replace your ground block with a two way splitter that costs more than $0.59.
2. Run an RG 6 cable from the splitter to your office being sure than the connectors and terminations are good.
3. If you have problems with your Internet connection and the levels on your modem are outside of spec call Comcast and have them fix the problem.

There is nothing about your setup or requirements that can't be accomplished and result in you having the best connection Comcast can or at least should provide.
 
While we debate how many angels can dance on the head of a pin do the following:
1. Replace your ground block with a two way splitter that costs more than $0.59.
2. Run an RG 6 cable from the splitter to your office being sure than the connectors and terminations are good.
3. If you have problems with your Internet connection and the levels on your modem are outside of spec call Comcast and have them fix the problem.

There is nothing about your setup or requirements that can't be accomplished and result in you having the best connection Comcast can or at least should provide.


i think thats the plan
 

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