Mains Powered Phones Causing ADLS Sync Loss & Slow Speeds

[delboyuk]

My F2S service was upgraded overnight / this morning from the 2MB service to the 'MAX ' service. At first it took over 10 minutes for my ADSL Router to sync - i had deliberately switched it off overnight, ready for the upgrade.

It finally synced at 4128kbs (as shown by the ADSL Router), despite BT estimating that only 3.5MB would be possible.

However, at this speed the sync would be lost when the main house phone was in use, and then a 10 minute delay whilst resyncing !!!

So, decided to hunt down the problem and started by unpluging the house phones. Circuit immediately synced at 7840kbps (as shown by the ADSL Router) - WOW - and remains stable. However, as soon as the house phone is plugged back in (using the ADSL splitter) the sync is lost again.

Tried the phone with different ADSL splitters, and different phone points around the house (there are 4 of these in total) - always the same problem - sync lost.

Also noticed that if the power supply to this phone was removed, the line would resync at 7840kbps and the phone could still be used, but without the LCD display and all the other/extra features like speed dials etc.. Plug the power back in and sync is lost again !!

Then decided to try a very basic/simple old BT phone instead (ie. one that doesnt have to be plugged into the mains). Guess what, the phone can be used without loss of sync at 7840kbps. Also, the ADSL Guide Speedtest shows actual download speed of 5842kbps (730KB/sec).

So, then tried a cordless DECT phone that needs a power supply- sync lost.

Therefore, it would appear that any phone requiring a mains power supply causes severe problems, whilst using 'old technology' phones is OK.

Anyone else had similar experience - or can explain this behaviour ?

Also, you may want to experiment yourself to see if unpluging your phones gives a major ADSL performance boost.

Del

[aos101]

I've remove your first post about this from this thread. If people post the same questions in multiple threads, it becomes difficult to keep track of replies.

[Aydon]

I found the same - I synched at 81xx with the DECT phone unplugged from the line, and only 5888 with it plugged in. The SNR was better as well.

[DomZ]

I've got a cordless phone downstairs that requires a mains adaptor, and it doesn't affect my DSL at all (when I was testing margins at the test socket (no phone plugged in) versus my extension upstairs with all phones around the house plugged in, I got the same line stats). Although note I am not on MAX yet.

My explanation to this problem would somehow the power is causing interference or something. But I dunno, never heard of this before.

[The Villan]

I don't have any problems either.

[Tim]

I haven't seen any difference removing or leaving the cordless phone in in the past.

Can't test now though (since the max regrade)

[BroomFondle]

If the phone's power supply is a switched mode one then its probably pushing hi-frequency noise onto the phone line.
I would have thought a decent adsl filter would have stopped that though

[John R]

Is the power block/cable running next to the phone cable ? If it is try routing so they take diffent paths.
I run a dect phone and the block and wires take a route diffrent to the phone cable. Also where the phone cable is routed to the spare room upstairs and is running along the same path as the eletrics i have shielded it, using some of the metal backed foam rubber used on copper pipes.
currently running at

System Uptime 14 hour(s) 2 minute(s)
Upstream Rate (Kbps) 448
Downstream Rate (Kbps) 7616
US Margin 16
DS Margin 2
Modulation T1413
LOS Errors 0
DS Line Attenuation 32
US Line Attenuation 63
Path Mode Fast Path

Forgot to turn router off overnight for upgrade, so did a quick reboot this morning and it picked up the 7 meg speed. Speed test showing f2s flying @ 529.94 KB/sec Magic..
This is despite BT saying around 3 to 4 meg max on my line. Still i'm sure it will drop due to the figures shown......

[Colster]

Originally Posted by John R

Is the power block/cable running next to the phone cable ? If it is try routing so they take diffent paths.
I run a dect phone and the block and wires take a route diffrent to the phone cable. Also where the phone cable is routed to the spare room upstairs and is running along the same path as the eletrics i have shielded it, using some of the metal backed foam rubber used on copper pipes.
currently running at


Forgot to turn router off overnight for upgrade, so did a quick reboot this morning and it picked up the 7 meg speed. Speed test showing f2s flying @ 529.94 KB/sec Magic..
This is despite BT saying around 3 to 4 meg max on my line. Still i'm sure it will drop due to the figures shown......

Notice you couldn't resist the temptation of the regrade button.

I'm sure it will drop regardless of the figures shown!

[delboyuk]

Originally Posted by BroomFondle

If the phone's power supply is a switched mode one then its probably pushing hi-frequency noise onto the phone line.
I would have thought a decent adsl filter would have stopped that though

Thanks BroomFondle. It would appear that a faulty (expensive) ADSL splitter/filter was the cause of the problem. When i tried using the (cheap/free) splitter/filter that came with the Origo ADSL Router it all worked OK.

So the 'dodgy' filter was working OK for my previous 2MB circuit, but obviously couldnt handle the faster 'MAX' regrade.

Thanks again. Del

[BroomFondle]

Originally Posted by delboyuk

... It would appear that a faulty (expensive) ADSL splitter/filter was the cause of the problem. ...

I'm probably using the same expensive Excelsus filter, the one that came out best in a review, so I'll bear that in mind when my Max regrade comes through..

[AndyBites]

Reviews of filters:
http://www.adslnation.com/support/filters.php

[delboyuk]

Originally Posted by AndyBites

Reviews of filters:
http://www.adslnation.com/support/filters.php

Many thanks for that. I had already checked this site out earlier today and have ordered the replacement BT Master Socket Face Plate (XTE-2005) which will give me better options/flexibility at a great price - delivery is usually next day - so fingers crossed.

[BroomFondle]

Originally Posted by AndyBites

Reviews of filters:
http://www.adslnation.com/support/filters.php

I used the review on this site because they publish comprehensive tech tests of each filter http://www.dslfilter.co.uk/products.asp

[Karl Prince]

Originally Posted by AndyBites

Reviews of filters:
http://www.adslnation.com/support/filters.php

Originally Posted by BroomFondle

I used the review on this site because they publish comprehensive tech tests of each filter http://www.dslfilter.co.uk/products.asp

Comparing these two reviews side by side makes interesting reading, with very different ratings for the same filters

Be good if people post make / models of filters, especially if they have tried more than one

[DomZ]

I've got the speedtouch ones, they seem fine to me to be honest.

[BroomFondle]

I'm in a very marginal area, many of my neighbours can only get 512k adsl but I just got 1Meg.
I originally tried no-name plug-in that came with my USR modem/router.
They were ok with one in use but poor with several. So I changed to Excelsius Z-420UK-A. There are 4 in use around the house, dect phones in two of them.

F2S adsl has been very solid since Sept-2004. Just got regraded today.
Currently very steady speed of 1700k down/488k up. Even if it sticks at that I won't be unhappy because my allowance also has doubled for the same cost.

[DomZ]

Out of curiosity BrromFondle what are your line stats? and distance from exchange?

[BroomFondle]

Originally Posted by DomZ

Out of curiosity BroomFondle what are your line stats? and distance from exchange?

From my USR9106 ADSL stat page:

___________Downstream Upstream
SNR Margin (dB): 6.6 18.0
Attenuation (dB): 63.0 31.5
Output Power (dBm): 11.9 16.7
Attainable Rate (Kbps): 1760 940
Rate (Kbps): 1728 448

4.5 miles by road to exchange. 6.4 Km as the crow files.

The annoying thing is there is a new exchange <.5km but thats only for the newer houses.

[andy12345]

OMG, Adsl nation's top-end filter is considered to be totally rubbish according to this previously mentioned link...

http://www.dslfilter.co.uk/products.asp

Have I completely missed something here or did most of you know that adsl nation's professional filter was supposedly rubbish???

Shock horror...

Has anyone with a technical background done proper tests as well on said filter????

[Johnno]

well I've been using ADSL nation ones since September 2003 and I've had zero problems with them, I have 3 but I did my wiring in a smart way where each phone has a splitter which is spurred off the main extension wiring and I still get 7MBps+ speeds, plus my voice quality is crystal clear. one thing though is my DECT phone is on the blink....tis really quiet compared to the BT corded phone we have.

[AndyBites]

A friend of my had adsl nation filters and found his connection dropping often @ 1mbps - turned out it was the dodge filters.. i directed him towards clarity (http://www.clarity.it/telecoms/adsl_bits.htm) and he's now stable as @ 1mbps.

Think these things make the most difference in the marginal areas.

shop:

http://www.clarity.it/xcart/home.php?cat=262

[BroomFondle]

Originally Posted by andy12345

Have I completely missed something here or did most of you know that adsl nation's professional filter was supposedly rubbish???

Has anyone with a technical background done proper tests as well on said filter????

That review has been around a long time, so yes I guess most of us knew.

They seem to have done a through technical test,

That why I bought 4 of the Excelsus ones. Had em some time now, no problems. I live is a very marginal area.

[trvlr]

I posted some info based on my own trouble-shoooting etc. (and input from Andrew, Chaz, JohnR et al) around a series of problems with symptoms that were sometimes similar to yours...; see:

http://www.freedom2support.net/forum...?t=4652&page=2

and also my post at the end of the above thread may be of interest/help;

There is a link there to an excellent house/phone-cabling reference/guide...

One filter in the Master socket - servicing both the router and the whole house slave/extension cct(s). may well resolve much of the problem... Certainly wouldn't hurt to try ? And as you have already discovered there are filters and filters...