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[richard]

Hi,

I'm experiencing a very annoying problem with my ADSL2+ connection and would greatly appreciate any helpful advice.

Since my connection was upgraded to ADSL2+ a couple of months ago, it experiences severe packet loss when my plasma television is turned on, and occasionally when my landline is called. The packet loss persists until the television is turned off or the router is restarted.

The problem occurs regardless of which telephone socket the router is connected to, except when the router is connected to the test socket, in which case the problem doesn't occur.

BT claim that there's no fault on my line, but I don't think they performed the test when the fault was occurring.

Unfortunately, replacing the television isn't a viable option because its mount and wiring are embedded in the wall.

The following is a typical sample of my modem's statistics, taken when the fault isn't occurring:

--------------------------- ATU-R Info (hw: annex A, f/w: annex A) -----------
   Running Mode            : ADSL2+(G.992.5)       State                : SHOWTIME
   DS Actual Rate          :  4809000 bps   US Actual Rate       :   971000 bps
   DS Attainable Rate      :  4536000 bps   US Attainable Rate   :   972000 bps
   DS Path Mode            :        Fast    US Path Mode         :        Fast 
   DS Interleave Depth     :       16       US Interleave Depth  :        1 
   NE Current Attenuation  :       45 dB    Cur SNR Margin       :        8  dB
   DS actual PSD           :    16. 9 dB    US actual PSD        :    12. 7   dB
   ADSL Firmware Version   : 232201_A 
  -------------------------------- ATU-C Info ---------------------------------
   Far Current Attenuation :       22 dB    Far SNR Margin       :        6  dB
   CO ITU Version[0]       : 00005000       CO ITU Version[1]    : 00000000
   DSLAM CHIPSET VENDOR    : < CTLM >

My SNRM falls to 6dB when the fault is occurring.

Is it normal for plasma televisions to create such powerful electrical interference? Is there any way of reducing the interference other than rewiring the house? I'm unsure of what action to take because I don't know who or what is ultimately at fault.

[orainsear]

Sounds like your TV is a source of REIN.

I experienced a similar problem a couple of years ago with a treadmill.  Basically when switched on the treadmill was propagating electrical noise through the house wiring and played havoc with the router.  I bought a Tacima CS929 main conditioner which has an earth line choke as well as some high frequency capacitors and choke.  With the treadmill plugged in to the mains conditioner the noise at the router was gone.

They can be bought for around £25, so if you think that the noise at your router could be reaching it via the house wiring it may be worth giving one a go.

Edit:

Although it could be the TV that's causing the problems, do you have a Sky box attached to your phone line?  If your router is OK when in the test socket that seems to suggest that it may not be the mains propagating the noise.

[HPsauce]

except when the router is connected to the test socket, in which case the problem doesn't occur.

That strongly suggests inappropriate or faulty extension wiring, which is definitely not BT's responsibility, it's yours I'm afraid. It's a very common occurence, especially with ADSL2+ which is more sensitive to interference.
Faulty wiring can and does act like a huge aerial collecting interference that disrupts the broadband signal.
Most (all?) ADSL2+ ISP's are pretty clued up on this and will have guides on optimising your wiring - who is your ISP?

[richard]

Sounds like your TV is a source of REIN.

I experienced a similar problem a couple of years ago with a treadmill.  Basically when switched on the treadmill was propagating electrical noise through the house wiring and played havoc with the router.  I bought a Tacima CS929 main conditioner which has an earth line choke as well as some high frequency capacitors and choke.  With the treadmill plugged in to the mains conditioner the noise at the router was gone.

They can be bought for around £25, so if you think that the noise at your router could be reaching it via the house wiring it may be worth giving one a go.

Thanks, I'll try one.

except when the router is connected to the test socket, in which case the problem doesn't occur.

That strongly suggests inappropriate or faulty extension wiring, which is definitely not BT's responsibility, it's yours I'm afraid. It's a very common occurence, especially with ADSL2+ which is more sensitive to interference.
Faulty wiring can and does act like a huge aerial collecting interference that disrupts the broadband signal.
Most (all?) ADSL2+ ISP's are pretty clued up on this and will have guides on optimising your wiring - who is your ISP?

How do I tell if my extension wiring is faulty?

My ISP is Demon. I'm planning to migrate to a different ISP when this problem is resolved because Demon's customer service has become appalling. It took them nearly a month for them to tell me that their was no detectable fault on the line and that I should contact BT.

[HPsauce]

Thanks, I'll try one.

Before you spend any money check out your wiring, it really is the most likely cause. 
Here's a good starting point: http://www.kitz.co.uk/adsl/socket.htm

[orainsear]

Before you spend any money check out your wiring

Yep good advice - no point in buying something if you don't need it.

When you are checking out your wiring pay particular attention to whether you have the ring wire connected.

[mr_chris]

Since it hasn't been said already, it may well be worth checking / replacing your filters and/or trying to ensure your telephone cable and router are far enough away from the television. Since it's also happening (albeit to a lesser degree) when you receive a phone call, it might be worth looking at your filters.

Some devices, particularly, but not limited to, Sky boxes and fax machines, sometimes require double filtering (plugging one filter into another) - everything and anything is worth a try.

It does look like your TV is causing a lot of interference though - and as you say replacing it isn't a viable option, given the cost and inconvenience involved!

Please report your findings back though - hope you manage to improve the issue somehow. Fingers crossed

[jid]

Do you have a telephone extension running past or near your TV.

If so it could be the cause. However as others have said, its most likely your extension wiring.

>> How do I tell if my extension wiring is faulty?

You found this out yourself as when you connected to the Test Socket the problems you were having disappeared.

[coolsnakeman]

do you have a Sky box attached to your phone line? 

As mentioned about the sky tv make sure you have this filtered correctly and not actually plugging into your phone socket without a filter as this will cause these issues. If this is fine then its more than likely your internal wiring as proved by connecting into the test socket and that is unfortunately your responsibility to maintain that is off course if you want to pay BT £125 or more to come out and fix it for you which i doubt that would interest you lol.

[richard]

Is it possible to shield the telephone extension wiring running near the television without rewiring the whole house?

[waltergmw]

Provided you can get access to your cable any length could be replaced with Cat 5 FTP (Foil {sheathed} Twisted pair).

However, how do you know which piece of cable is actually picking up the noise?

I suggest some noise source investigations followed by their elimination would possibly be a better apparoach.
Kind regards,
Walter

[richard]

Removing the bell wire stopped the television from disrupting the connection, but not incoming telephone calls. It also significantly increased my downstream speed.

So much for BT's claim that installing an I-Plate has the same effect as removing the bell wire!

[jeffbb]

Hi
Good news TV now ok .  

Telephone still a problem this link shows filter connection options

this link may assist with phone interference troubleshoot

Regards Jeff

[sevenlayermuddle]

So much for BT's claim that installing an I-Plate has the same effect as removing the bell wire!

Actually, an iPlate really should have the same effect as removing the bell wire.  I'm sure I'm not alone in being interested as to why, in your case, it wasn't so.

One possible suggestion... did you disconnect the bell wire at all sockets, or just the master?  It's the master that matters most, though some folks argue for it to be removed at all sockets.

The thing is,  it's not uncommon to find that a property has more than one master socket installed, if that's all the builder had left,  in the mistaken belief it will do no harm.  Actually, it has several drawbacks for ADSL, most notably the fact that it will 'undo' the effect of an iPlate, or of disconnecting the bell wire at the master alone.   But disconnecting from all sockets would mask the effects of a second master.     So, if you disconnected at all sockets, is there any chance there's more than one master socket (recognised by having the capacitor on the PCB)?

[waltergmw]

Just to amplify 7LM's note on the capacitor in Master Sockets; note that as well as the split front plate type, they can be single or twin wall plate sockets or even the small surface mount box.

Kind regards,
Walter