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Coax Splitters

TemjinGold

Diamond Member
My house has 4 coax lines (three on second floor, 1 on first in living room) and a ethernet jack in dining room (using this as office.) Originally, the plan was to plug my computer into the ethernet and keep the cable modem and router hooked up in the basement. The problem is, doing so drops my UL from 6 mbps to 1mbps or less (both verified through Xfinity Speed Test).

When I plug the modem and router into the computer upstairs directly (by borrowing the coax jack in the living room), speeds are fine. It seems the easiest way is to get a coax splitter for the coax jack in the living room (since that one is also for my TV.) Here's what I'm wondering:

1) Is there a reason why the ethernet setup has greatly nerfed speeds? If I could use that, that would be the simplest solution.

2) The 4 coax cables are already feeding into a 4-way splitter in the basement. If I get a splitter for the living room to use both modem and TV, is there a certain type of "higher quality" splitter I can use in both cases to reduce the signal loss?

3) Is there another solution I haven't considered? (Local company wants $125 to add a new jack to the dining room, which is a bit steep.)
 
I use splitter, one goes to cable modem and another goes to TV, works fine, I have not seen any speed difference.
I dont know why, my I myself have also experienced very good speeds over Ethernet compared to wireless. Also the connection will be more stable too, no drops.
Another solution could be to use Ethernet over power adapters!
 
I'm sorry, do you mean to say that one of your coax cables is going to the basement? What did you connect your modem to before moving it? I'm assuming there's a panel in the basement where you plug the router into your installed Ethernet cables to be distributed to the wall jacks.

If that's the case, then I'd suggest bringing a laptop down there to plug directly into the router to try out the connection of that coax line without the installed Ethernet cords and wall jacks in the loop.

If it's still bad (or if you don't want to move your computer down there) I'd call the ISP and complain about the slow upload speeds. They can send a tech out to check the signal strength of the different coax jacks. They may identify a bad coax cable or some such and have it fixed for you. Worst case scenario they can tell you if you have a strong enough signal strength to use another splitter in your living room.
 
My house has 4 coax lines (three on second floor, 1 on first in living room) and a ethernet jack in dining room (using this as office.) Originally, the plan was to plug my computer into the ethernet and keep the cable modem and router hooked up in the basement. The problem is, doing so drops my UL from 6 mbps to 1mbps or less (both verified through Xfinity Speed Test).

When I plug the modem and router into the computer upstairs directly (by borrowing the coax jack in the living room), speeds are fine. It seems the easiest way is to get a coax splitter for the coax jack in the living room (since that one is also for my TV.) Here's what I'm wondering:

1) Is there a reason why the ethernet setup has greatly nerfed speeds? If I could use that, that would be the simplest solution.

2) The 4 coax cables are already feeding into a 4-way splitter in the basement. If I get a splitter for the living room to use both modem and TV, is there a certain type of "higher quality" splitter I can use in both cases to reduce the signal loss?

3) Is there another solution I haven't considered? (Local company wants $125 to add a new jack to the dining room, which is a bit steep.)

first question. is the splitter 1 to 4 a powered or passive splitter?

if it is passive look into this powered one.



http://www.amazon.com/gp/product/B00...ls_o01_s00_i00




I have that 4 way splitter. 1 coax goes to the modem then router then 2 8 port switches .

the other 3 coax cables go to 3 cable boxes. works well.


next the mystery ethernet jack. where is the router?


if there is one coax into a 4 way splitter .


with 4 coax cables coming out the one of those coax cables must go to a router. where is that router?

you kind of need to know how the ethernet jack works.

test by disconnecting all four coax cables at your 4 way splitter. then add them back until the e-jack works.
 
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Thanks for the advice. There is a box in my basement that has 4 coax cables (one for each coax jack in the house) going into a passive splitter. The way it was originally set up was main line going into a 1->2 splitter. One of these ends went straight to the modem while the other went to the IN of a 4-way. The router sat in the basement and the other end of the ethernet jack went into the router there.

I moved the router and modem up to the first floor and removed the 1->2 splitter. This leaves the main line going straight into the 4-way (instead of going into the 2-way) and I put the 2-way on the coax jack at the wall in the living room. This seems to be working fine albeit I have a ton of cables running across the floors of the two rooms now.
 
Just note that not all splitters are equal, and I'm not talking about quality. They are sold at different frequency ranges. In addition, I don't know if it actually matters but I read somewhere once that if you use splitters you should make sure that all ports are used. I.e. don't buy a 4-way splitter if you only need 2 or 3. Again, I'm not saying it actually matters.

As to your modem, every modem has a access ip just like your router that you can usually get into to check signal strength. Research your particular modem online to find it. That should give you a definitive answer on signal strength.
 
Thanks for the advice. There is a box in my basement that has 4 coax cables (one for each coax jack in the house) going into a passive splitter. The way it was originally set up was main line going into a 1->2 splitter. One of these ends went straight to the modem while the other went to the IN of a 4-way. The router sat in the basement and the other end of the ethernet jack went into the router there.

I moved the router and modem up to the first floor and removed the 1->2 splitter. This leaves the main line going straight into the 4-way (instead of going into the 2-way) and I put the 2-way on the coax jack at the wall in the living room. This seems to be working fine albeit I have a ton of cables running across the floors of the two rooms now.


if the new way works good. you can always try a powered one down the road.

what is the router?

what is the modem? motorola? scientific atlanta? cisco?

http://www.cisco.com/web/about/ac49/ac0/ac1/ac259/scientificatlanta.html

http://www.cisco.com/web/consumer/support/modem_DPC2100.html


you may have this one you can look for how to find signal strength


what cable company?



Just note that not all splitters are equal, and I'm not talking about quality. They are sold at different frequency ranges. In addition, I don't know if it actually matters but I read somewhere once that if you use splitters you should make sure that all ports are used. I.e. don't buy a 4-way splitter if you only need 2 or 3. Again, I'm not saying it actually matters.

As to your modem, every modem has a access ip just like your router that you can usually get into to check signal strength. Research your particular modem online to find it. That should give you a definitive answer on signal strength.



yeah try to find the signal strength. 0 is very good -10 is borderline. (general rule of thumb )
 
first question. is the splitter 1 to 4 a powered or passive splitter?

if it is passive look into this powered one.



http://www.amazon.com/gp/product/B00...ls_o01_s00_i00




I have that 4 way splitter. 1 coax goes to the modem then router then 2 8 port switches .

the other 3 coax cables go to 3 cable boxes. works well.


next the mystery ethernet jack. where is the router?


if there is one coax into a 4 way splitter .


with 4 coax cables coming out the one of those coax cables must go to a router. where is that router?

you kind of need to know how the ethernet jack works.

test by disconnecting all four coax cables at your 4 way splitter. then add them back until the e-jack works.


You have to be careful when using powered devices with cable modems, they need to be a certain type to be effective. What most people miss out on is the fact that they need to be powered on the upstream as well, otherwise they wont get back to the CO properly. Motorolla makes one for specifically this purpose

http://www.amazon.com/Motorola-Signa...odem+amplifier
 
You have to be careful when using powered devices with cable modems, they need to be a certain type to be effective. What most people miss out on is the fact that they need to be powered on the upstream as well, otherwise they wont get back to the CO properly. Motorolla makes one for specifically this purpose

http://www.amazon.com/Motorola-Signa...odem+amplifier

you are correct . mine is more for cable tv then a modem.
 
Whoa... never run a cable modem through a powered splitter if you avoid it. If you do get one speced for cable modems. Make sure the 1:2 splitter is 1ghz or 2ghz depending on your providers plant. Plug the modem in there connect to it via a PC and pull the signal strengths. Speed tests test your inside cabling. If the Ethernet is poorly installed you can have issues with performance that isn't the modems fault. Also a crappy splitter can wreck the upstream. Some older passive splitters don't allow much of the upstream to get out. They can be filtered etc.
 
Appreciate the help, guys. The "lots of cables on the floor" method is working fine at the moment so I'll stick with that for now. If it stops working fine, I'll be coming back here for this solution. 🙂
 
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