Guidance on noise margins.

Scottyboy · Aug 02, 2011, 21:09:44

Hello, old member not posted in sometime. I have just moved property, back into a house I once lived and needed assistance from here. Turns out I had an alarm system wired into master socket causing noise.

Anyway, ive just plugged my router in direct to master socket and showing following and wondered if they are ok or signs of potential problems.

Down rate 6238kbps
Down margin 6db
Down attenuation 51

Up rate 1011kbps
Up margin 6db
Up attenuation 30

When I plug filter and phone in values are

Down rate 4259kbps
Down margin 6db
Down attenuation 58

Up rate 955kbps
Up margin 6db
Up attenuation 33

Thanks in advance as I know Im gonna find the asnwers here :-)

Steve · Aug 02, 2011, 22:10:37

The line degrades when you plug the filter and phone in,I think you need to swap filters and phone if possible. Also how is the phone connected to the master socket ie wired extension lead or phone cable (no extension) to filter.

Scottyboy · Aug 02, 2011, 22:28:02

Hi Steve,

as I have just moved in Im doing this is from scratch since had previous problems in this property. So im only working directly connected to the master socket for now and there is no other telephony equipment plugged in. There are 2 extension sockets in the house which have nothing connected.

Master Wall Socket - Filter - Telephone Directly into filter and Router into filter.

I should add my Idnet line only went active today at this new property so expect the speed to settle over time, my main concern was should I be worried about the noise margins or attenuation levels for my connection?

thanks

Steve · Aug 02, 2011, 22:37:18

The initial connection with router alone looks great for that attenuation.As soon as you plug the phone in, the line appears longer as the attenuation rises to 58 and you get an equivalent reduction in sync.Both sets of stats are ok but it would be good to find out why there is such a marked difference.Rik may have some thoughts on the matter tomorrow?

Scottyboy · Aug 02, 2011, 23:12:11

I think I have a problem with the wiring in the face plate. My previous tennents may have been messing about, as my extension cables do not function and some of the bt cables were not connected so I tried to reconnect. However, I dont have a clue so I have taken said cables out again to leave the plate as I found it.

Now with filter and telephone connected via the faceplate I get the same readings as directly into master socket. Think I can live without the extensions for now.

Will let the line settle and see how we go. Cheers

Rik · Aug 03, 2011, 09:31:24

Can you take a picture of the master socket with the faceplate off and the wires that are available for connection?

cavillas · Aug 03, 2011, 09:40:49

I thinbk it's also advisable to put a filter into each of the extensions whether they are being used or not. My friend hadtwo extensions not in use and when he put filters in themhe got a much faster and stale connection.

Scottyboy · Aug 03, 2011, 11:40:25

Hi Rik, I was looking at one of my old posts, pretty much same situation! dejavu. See below picture of the face plate, so I have at the moment got phone and router plugged directly into the master socket via filter, you can see the wires that are not connected to the faceplate. When I first removed it the only wire connected was the orange wire which I believe is the Ring/Bell wire. I have no idea about the telephone wires so I am assuming the disconnected wires are the extenions or the burglar alarm which I have no contract with but is currently displaying a "telephone line" trouble alert.

this is my router info as off right now

DSL Status : Up
DSL Modulation Mode : NOT TRAINED
DSL Path Mode : INTERLEAVED
Downstream Rate : 5907 Kbps
Upstream Rate : 1035 Kbps
Downstream Margin : 2 db
Upstream Margin : 6 db
Downstream Line Attenuation : 51
Upstream Line Attenuation : 30
Downstream Transmit Power : 0
Upstream Transmit Power : 0

I seem to be able to surf the net just fine at the moment, but have not set up my home network or ps3 yet and want to make sure Ive eliminated any potential issues before I get to that. And Ive no idea if the above readings are acceptable or not.

I should add that I have a Linksys WAG354G

Uploaded with ImageShack.us

Rik · Aug 03, 2011, 11:43:15

You're right, everything has been disconnected, so you should be able to put the faceplate back on and get similar results as with the test socket.

Scottyboy · Aug 03, 2011, 11:47:47

ah thanks.

So the noise margin of 2db should not be an issue? I thought the higher this value the better and that maybe below 6 would be problematic?

Rik · Aug 03, 2011, 11:50:11

Your current d/s margin appears to be 2db, so wherever the noise is coming from, it isn't your internal wiring. The not trained worries me slightly, though, it would normally indicate no connection.

Scottyboy · Aug 03, 2011, 12:01:54

yeah I wondered about the "not trained" could that be down to router firmware? I havent upgrade the router in sometime. So it is perhaps functioning but just not updated to display correct info?

I have swapped the ADSL filter. Now showing below.

DSL Status : Up
DSL Modulation Mode : NOT TRAINED
DSL Path Mode : INTERLEAVED
Downstream Rate : 6286 Kbps
Upstream Rate : 1008 Kbps
Downstream Margin : 6 db
Upstream Margin : 6 db
Downstream Line Attenuation : 51
Upstream Line Attenuation : 30
Downstream Transmit Power : 0
Upstream Transmit Power : 0

Rik · Aug 03, 2011, 12:44:13

That's looking a lot healthier. Keep an eye on the NM, see if it fluctuates much. A firmware upgrade is definitely worth trying.

jameshurrell · Aug 03, 2011, 12:48:55

Quote from: Scottyboy on Aug 03, 2011, 12:01:54
DSL Status : Up
DSL Modulation Mode : NOT TRAINED
DSL Path Mode : INTERLEAVED
Downstream Rate : 6286 Kbps
Upstream Rate : 1008 Kbps
Downstream Margin : 6 db
Upstream Margin : 6 db
Downstream Line Attenuation : 51
Upstream Line Attenuation : 30
Downstream Transmit Power : 0
Upstream Transmit Power : 0

On those stats I would leave alone now... they are very good for the attenuation. On my 54db line, I only manage a sync of 3600Kbps

Scottyboy · Aug 03, 2011, 18:38:09

Thanks guys.