Low upstream SNR

Hi, Can someone help me?

I recently fitted an adsl nation XTE-2005 faceplate:
http://www.adslnation.com/products/xte2005.php

The BT drop line comes into the property, outside, into a box attached to the conservatory. From there there is a line that goes inside the house and into the master socket.

Th extensions in the house are connected before the master socket, in the cellar, and go into one line that then goes into the master socket. These include the alarm and other phones.

I am on BE.

According to : http://www.kitz.co.uk/adsl/adslchecker.php the distance from the exchange

Direct: 1.39 km
(appx)* By Road: 2.57 km

Here are my router stats:
[img=http://img193.imagevenue.com/loc504/th_52361_screeen_122_504lo.jpg]

DSL Connection

Link Information

Uptime: 0 days, 2:22:24
DSL Type: G.992.5 annex A
Bandwidth (Up/Down) [kbps/kbps]: 1,239 / 8,186
Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00
Output Power (Up/Down) [dBm]: 12.0 / 19.0
Line Attenuation (Up/Down) [dB]: 23.0 / 41.5
SN Margin (Up/Down) [dB]: 6.5 / 8.0
Vendor ID (Local/Remote): TMMB / BDCM
Loss of Framing (Local/Remote): 45 / 0
Loss of Signal (Local/Remote): 5 / 0
Loss of Power (Local/Remote): 0 / 0
Loss of Link (Remote): 0
Error Seconds (Local/Remote): 4 / 0
FEC Errors (Up/Down): 7 / 22,190
CRC Errors (Up/Down): 7 / 6
HEC Errors (Up/Down): 6,697 / 1

Before I changed this new faceplate, I was getting a higher speed (about 9500)and the downstream SNR was 6.5 or 7 at that speed; and I don't remember my upstream SNR being that low. Can someone tell me what determines the upstream SNR (why it could have lowered?) Is this what is now determining the low speed?

Th extensions in the house are connected before the master socket, in the cellar, and go into one line that then goes into the master socket. These include the alarm and other phones.

I can't understand why you fitted a filtered socket ? All your phones are connected before the filter. That's why your upstream noise margin is so poor.

Your extensions need to be wired off the new faceplate, not before as now. Does the alarm have an ADSL filter on it?

If not then then the connection speed you are getting is pretty amazing.

Upstream SNR margin will vary, and a phone on the line can make it lower. The margin is not bad on the upstream, to judge anything we need to know what it was before, and the upstream sync speed, because the two are linked, i.,e. higher sync speed usually means lower noise margin.

(In response to Zebedee)

Not all the lines. There is the one that goes direct into the ADSL bit on the master faceplate from the Bt drop line outside the house (it isn't connected direct into the house).

Only the extension lines are connected before the faceplate into one line (in the cellar) so that only one line goes into the phone bit on the faceplate.

Edited by Purewater (Wed 09-Dec-09 10:40:42)

Now I am confused...

How many telephone numbers do you have?

If one, then all the lines are effectively the same line in ADSL terms. And thus need filters.

There is just one telephone line. The BT drop line comes into a box attached to the exterior of the conservatory outside. From there there is a direct line which goes under the cellar up through the floor into the adsl portion of the master faceplate in the house. The other phone lines are twisted together into one line under the cellar which goes into the phone portion of the master faceplate.

I thought the ADSL nation faceplate separated out the adsl from the phone?

Currently we have wireless phones. With handsets all over the house. The phone basestation is connected to the phone socket of the faceplate. The router is connected to the ADSL socket on the faceplate. Currently I am not using a filter for the phone and everything still works .

The alarm is for when it goes off - it calls someone - the police or someone (I'm not sure).

The other phone extensions are for sky, when we need it connected to watch a movie. They are not connected to any appliances currently.

In reply to a post by Purewater:

I thought the ADSL nation faceplate separated out the adsl from the phone?

Err, no. The ADSL is connected direct to the line. The filter serves two purposes - to prevent phones from loading down the ADSL signal, and to prevent the ADSL signal from reaching the phones.

ALL devices (other than the ADSL router itself) have to be connected via filters or a filtered faceplate. That includes DECT phone bases, fax machines, telephone answering machines, burglar alarms, and Sky boxes. If you don't, everything will still work, but speeds may be reduced. Sounds like you have some devices connected via filters, and some not.

If the alarm is wired to the phone side of the ADSL faceplate then it is filtered, and OK but even though it is not calling anyone it needs to be filtered to avoid any effect

The new description reads like most stuff is filtered, which is good.

Just re the ADSL Nation XTE-2005, I installed one of those recently on mt 51dB line. Plus one of their high quality ADSL cables.

There are no extensions.

The result was a small decrease in connection speed, verified by several swaps in and out.

It and the ADSL cable are now back in their jiffy-bag.

In reply to a post by Purewater:

From there there is a direct line which goes under the cellar up through the floor into the adsl portion of the master faceplate in the house. The other phone lines are twisted together into one line under the cellar which goes into the phone portion of the master faceplate.

How can this be?

The input to the master socket is just a 'phone line carrying both the adsl and voice signals. There is no adsl portion and phone portion on the input side. It is on the output side that they are separated, by a filter.