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FusionOnRGYB
@sonic.net

FusionOnRGYB to leibold

Anon

to leibold

Re: Did not think that interior wiring made such a big differenc

There are sets of two wires coming off the NID for phone service, one was reg green/yellow black that services the phone in the front of the house and a Cat3 that runs about 3/4 the way to the back where it splices into another 4-color wire that services two bedrooms (one used as an office). I suspect this was added on later as a repair so there is still another 30 or 40 ft of red-green wire from this junction as it follows the base board to where the modem was previously plugged.

You said that any point where the copper is discontinuous causes reflections. Does that mean if wires are soldered rather than connected with the gel-filled Scotchlok connectors there will be less reflections?

As it stands here's how the setup looks:

NID -> UTP cross connect wire -> DSL Splitter -> flat phone cable -> keystone -> Cat5e -> keystone -> flat phone cable -> modem

I've removed the biggest offenders to the DSL signal, but if I replace both pieces of flat phone cable with Cat3 will there be any significant improvement at this point? The section between the modem and jack is about 6 to 7 ft from a dimmer. I have a 25-ish foot section of Cat 3 I was using for phone cord that I made. I have the connectors and tools to attach RJ12 connectors and RJ45.

The DSL splitter has the option of using screw posts or mod-plugs for all three connections, is there advantage to using either side?

DaneJasper
Sonic.Net
Premium Member
join:2001-08-20
Santa Rosa, CA

DaneJasper

Premium Member

For best performance and reliability, eliminate all flat phone cable - six feet or less of it is "okay", but even that isn't ideal. (Our new modems include a 12 foot twisted-pair line cord.)

-Dane

FusionOnRGYB
@sonic.net

FusionOnRGYB

Anon

For clarity, you mean to eliminate any flat cable for the modem right?

I'm thinking it should not matter for anything on the voice side of the splitter like my fax.

leibold
MVM
join:2002-07-09
Sunnyvale, CA
Netgear CG3000DCR
ZyXEL P-663HN-51

leibold to FusionOnRGYB

MVM

to FusionOnRGYB
said by FusionOnRGYB :

You said that any point where the copper is discontinuous causes reflections. Does that mean if wires are soldered rather than connected with the gel-filled Scotchlok connectors there will be less reflections?

Any splicing regardless of method will cause some small amount of signal degradation and reflection. The idea is to keep the number of splices low and not necessarily to worry too much about which method of splicing is better. The gel-filled connectors are fine and this is what I used too.
The same applies to the question of screw contacts versus modular plugs. The difference is probably small enough to use whatever is more convenient.
said by FusionOnRGYB :

I've removed the biggest offenders to the DSL signal, but if I replace both pieces of flat phone cable with Cat3 will there be any significant improvement at this point?

It would certainly be better if those two sections were twisted pair cable as well but it is hard to say whether it would improve your speed significantly (or at all). It will mostly make your line more resistant to interference from external noise. However if there isn't any such noise causing interference right now it could mean a lot of effort and no gain in performance to show for it.

FusionOnRGYB
@sonic.net

FusionOnRGYB to FusionOnRGYB

Anon

to FusionOnRGYB
I was digging around and the phone cable that came with my old AT&T modem is round rather than flat. Is this necessarily Cat3?

leibold
MVM
join:2002-07-09
Sunnyvale, CA
Netgear CG3000DCR
ZyXEL P-663HN-51

leibold

MVM

There is no guarantee that a round phone cable actually consists of twisted pairs.
Ideally if it came with a DSL modem it should be a twisted pair cable but it would not surprise me if some vendors would cut corners even there.
Quality cable will have certifications and ratings printed along the length of the cable.

FusionOnRGYB
@sonic.net

FusionOnRGYB

Anon

Replacing the flat cable from the splitter to the Cat5 with Cat3 with RJ11 on one end and bare wire into screw post terminal on the other made no difference according to the line stats. I don't know what I was expecting to see, but I suppose increased resistance to noise is a good thing since I cannot predict it. All my findings are on quiet Saturday evening and Sunday afternoon when the nearby laundry machines and fluorescent lights were not operating.

As for the round phone cord, the only thing I can make out is "TIA568B2" and "Cat.5 28AWG". I put this between the wall jack and the modem and compared to flat cable, I did not notice any difference.

Here is Cat3 from the splitter to the Cat5e
»i.imgur.com/0SdsZ.png

Flat cable at the same location.
»i.imgur.com/XTY8L.png

leibold
MVM
join:2002-07-09
Sunnyvale, CA
Netgear CG3000DCR
ZyXEL P-663HN-51

leibold

MVM

It did have a measurable impact after all, even if it is only a 0.2dB improvement in noise margin (every little bit helps) and a slightly higher attainable rate (theoretical maximum speed).

The TIA568B2 indicates that the cable conforms to EIA/TIA specification 568B with the suffix 2 indicating that the cable only has 2 instead of the normal 4 pairs. Cat.5 means that this is a twisted pair cable meeting the tighter specifications for Cat5 cable. 28AWG is the size of each copper wire. This is definitely a good cable to use for your DSL modem.

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA
TP-Link TD-8616
Asus RT-AC66U B1
Netgear FR114P

NormanS to DaneJasper

MVM

to DaneJasper
said by DaneJasper:

For best performance and reliability, eliminate all flat phone cable - six feet or less of it is "okay", but even that isn't ideal. (Our new modems include a 12 foot twisted-pair line cord.)

That reminds me: GF has a six-conductor flat phone cable to the NID. Strangest thing I ever saw, and terminated with a 6P6C plug (I learned that terminating all six is called, "RJ-25")!

I brought over some remainder CAT-5e cabling from wiring my mother's house. I still need to replace that RJ-25 run with the CAT-5e.

DaneJasper
Sonic.Net
Premium Member
join:2001-08-20
Santa Rosa, CA

DaneJasper

Premium Member

We have seen customers use 50 foot Radio Shack "telephone extension cable" to hook up their DSL modem - result is really, really poor performance. Twisted pair is best, and we suggest a maximum of six feet (a typical line cord) of "flat satin".

FusionOnRGYB
@sonic.net

FusionOnRGYB to leibold

Anon

to leibold
Thanks for the help leibold! My line is about as good as I care to make it. I did not think that 0.2dB makes any difference because I think that number tends to fluctuate.

I guess another option would be to plug the modem into the splitter and then use the wire run I made for fast Ethernet to the router.

BTW, are the red/green and yellow/black cables twisted pair?
FusionOnRGYB

FusionOnRGYB to NormanS

Anon

to NormanS
I used 6P6C flat phone cables at my last job for digital telephones. The 6P4C cables did not work for those phones.

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA

NormanS to FusionOnRGYB

MVM

to FusionOnRGYB
said by FusionOnRGYB :

BTW, are the red/green and yellow/black cables twisted pair?

Not as far as I know. I think it is also called, "station wire", and has no "twist" standard.
drizzle
join:2002-06-14
Palo Alto, CA

drizzle to FusionOnRGYB

Member

to FusionOnRGYB
said by FusionOnRGYB :

I guess another option would be to plug the modem into the splitter and then use the wire run I made for fast Ethernet to the router.

this sounds like a good option - placing the modem at the NID
bswp
join:2010-11-28
Berkeley, CA

bswp to FusionOnRGYB

Member

to FusionOnRGYB
"I guess another option would be to plug the modem into the splitter and then use the wire run I made for fast Ethernet to the router."

Sure, but if your modem is the ZyXel with wifi that Sonic provides for Fusion service, then you may have issues getting the signal where you want it. OTOH, if you just run fast ethernet to a router w/ wifi, good to go.