Kitz ADSL Broadband Information
adsl spacer  
Support this site
Home Broadband ISPs Tech Routers Wiki Forum
 
     
   Compare ISP   Rate your ISP
   Glossary   Glossary
 
Please login or register.

Login with username, password and session length
Advanced search  

News:

Author Topic: Using Custom Leads  (Read 5025 times)

soms

  • Reg Member
  • ***
  • Posts: 537
Using Custom Leads
« on: July 18, 2007, 11:55:49 AM »

Hi all,

This is my new little project, to determine if a home made lead can help improve ADSL performance on marginal lines.

We have all seen the RJ11 leads bundled with routers, they tend to be 2 core or 4 core flat leads, anything from 1 to 2 metres long. Unfortunately this type of lead isn't really ideal for ADSL, or at least is no help on long, marginal lines.

In the past I tried a belkin hi-speed shielded lead, but this was very springy, cumbersome etc and made cable management very difficult. In more recent times with the Home Hub, I swapped out a shortened flat lead for a twisted pair one and the sync speed was improved by around 200-300k when it resynced.

Until now I have used a shortened flat lead, where I cut off a BT connector and crimped on an RJ-45 lead. Since the router was right beside the NTE5 faceplate this seemed like a plan.

Now I have received a new RJ11/RJ12 crimp tool and some connectors so plan to do a few custom leads.

For my first trial I have taken a piece of CW1308 twisted pair cable, about 40cm in length, pulled out the wires and just slipped the blue pair back into the sheath.

(you could wire it 4 core with RJ-11 connectors or 6 core with RJ-12 connectors but I am not sure on wiring configurations for RJ connectors, especially when you compare both ends)

Then I crimped some connectors onto the blue pair. Mimicking other leads I have seen I swapped the pair over at one end of the cable.

I have proved the lead works fine using a phone but have yet to try get the DSL down it (everyone being online and that).

Cable was proved using PSTN socket > RJ-11 adapter > RJ-11 lead > RJ coupler > US to UK phone adapter > phone

Hopefully will see a sync increase. Using Linksys WAG354G at the moment, it works again now.

Just need to wait til the folks are offline.

Be interesting to see if it does work. It is such an easy thing to do, took about two minutes. You have to wonder why manufacturers dont supply twisted cables. This one is very flexible, very almost like flat cable with only a single pair inside the sheath.

*EDIT*

- It seems regular 6 core twisted pair cable doesn't actually fit into the RJ11 or RJ12 connectors. The cable is two fat.
 4 pair twisted does fit.
- the use of a butt phone reveals that actually swapping the pair at one connector reverses the polarity whereas if the connectors are wired identically at each end there are kept straight

- on swapping the leads over the sync rate remains the same however downstream margin has increased by 1dB. I expect on a longer lead there might be a more noticable difference.
« Last Edit: July 18, 2007, 12:29:28 PM by soms »
Logged

roseway

  • Administrator
  • Senior Kitizen
  • *
  • Posts: 40928
  • Penguins CAN fly
    • DSLstats
Re: The Custom Cable Project
« Reply #1 on: July 18, 2007, 12:31:21 PM »

I'll be interested to see the results. For geographical reasons I have to use a 3m cable to my router, so a better cable might make a real difference.
Logged
  Eric

kitz

  • Administrator
  • Senior Kitizen
  • *
  • Posts: 33035
  • Trinity: Most guys do.
    • http://www.kitz.co.uk
Re: Using Custom Leads
« Reply #2 on: July 18, 2007, 12:53:30 PM »

Interesting soms.

Whilst 1dB may not seem much and it wont do much for speed, it could however make the difference between stability on some lines.
Like you say could prove more interesting on longer lengths of cable where the benefits could be greater.

If anyone wants to try this and report their findings it would be great.

My own line isnt the best for playing around with stuff like this.  Im running on a 30m length of cheapy phone extension cable from argos and it doesnt make the slightest difference here. 
What I find highly amusing is that I strongly suspect that the said cable has also been nicked when I had new stair carpet laid.. and it causes a problem if I plug in a certain phone (it constantly rings) upstairs.  Yet my router reports the same stats whether using the extension or from the test socket behind the NTE5.
However when even higher speeds do come into effect then I can imagine things like this will make more of a difference.
Logged
Please do not PM me with queries for broadband help as I may not be able to respond.
-----
How to get your router line stats :: ADSL Exchange Checker

soms

  • Reg Member
  • ***
  • Posts: 537
Re: Using Custom Leads
« Reply #3 on: July 21, 2007, 09:15:26 PM »

Well after a few days of use I can say that the connection has proven very stable.

We had a full power off the other day as I was fitting a new spur power socket and when the router came back up it resynced at 1376K as has held a steady 9dB margin ever since (well, at least whenever I check).

Slightly off topic - this obviously shows that the target SNR margin is set at 9dB which I dont really mind in itself as I was receiving 1000K profile. Unfortunately, a several days ago there was some kind of drop out at the router went down to something around 400K downstream and even after all these days I am getting downloads at around 28Kb/sec. I am guessing stuck IP profile but cant be sure as I dont have Java on this PC so cant go on the speedtester right now. Its a pain as I am downloading a free game trial which is 1.4GB. I started it going before 2pm today and so far it has done 52%  ::)
Logged

kitz

  • Administrator
  • Senior Kitizen
  • *
  • Posts: 33035
  • Trinity: Most guys do.
    • http://www.kitz.co.uk
Re: Using Custom Leads
« Reply #4 on: July 22, 2007, 08:52:59 PM »

>> several days ago there was some kind of drop out at the router went down to something around 400K downstream and even after all these days I am getting downloads at around 28Kb/sec.

Does indeed seem like you have a 250 kbps IP profile. :(  Hope it sorts soon.
Logged
Please do not PM me with queries for broadband help as I may not be able to respond.
-----
How to get your router line stats :: ADSL Exchange Checker