Line Attenuation - what affects it?

[psychocandy]

From what I understand this is pretty much the thing that determines what your 'possible' max speed will be (allowing for acceptable line noise). Is this right?

What affects attenuation?

1. Distance from exchange?
2. Wiring from exchange?
3. Modem connected to phone extension in house? Will this make a significant difference as opposed to connected directly to master socket? (Or does this just increase line noise?)
4. Different modems? how does the one supplied (Netgear) compate to others?

Would be interested in different peoples findings here.

At the moment, I've got an extension lead running from the master socket upstairs where the modem is plugged in.

Getting attenuation of 63.5 but only syncing at aroud 1Mb maximum...

[dq1]

1, 2 and 3. If you plug the modem into your master test socket (assuming you don't have a very old BT installation) you will get the best attenuation you can get in your house if the difference is significant you may be able to help by rewiring your extensions.

Any remaining attenuation will be to do with your line to the exchange and I'm not sure what you can do about that.

Attenuation.............Approximate Line Length............Potential Connection Speed
32db...................................2.3km...... ...............................16000kbps
35db...................................2.5km...... ...............................14500kbps
40db...................................2.9km...... ...............................11800kbps
45db...................................3.2km...... .................................8500kbps
50db...................................3.6km...... .................................6500kbps
55db...................................4.0km...... .................................4500kbps
60db...................................4.3km...... .................................3200kbps
65db...................................4.7km...... .................................2000kbps

On this chart you see you should be able to get at least 2MB. Which means there is noise on your line preventing the max speed. You could try to reduce noise on your line by either:
Removing the ring wire on your extensions
Installing a filtered master face plate
Rewiring your extension with Cat5e cable or higher

see:

http://www.skyuser.co.uk/forum/cabli...r-results.html
http://www.skyuser.co.uk/forum/cabli...ace-plate.html

[psychocandy]

1, 2 and 3. If you plug the modem into your master test socket (assuming you don't have a very old BT installation) you will get the best attenuation you can get in your house if the difference is significant you may be able to help by rewiring your extensions.

Any remaining attenuation will be to do with your line to the exchange and I'm not sure what you can do about that.

Attenuation.............Approximate Line Length............Potential Connection Speed
32db...................................2.3km...... ...............................16000kbps
35db...................................2.5km...... ...............................14500kbps
40db...................................2.9km...... ...............................11800kbps
45db...................................3.2km...... .................................8500kbps
50db...................................3.6km...... .................................6500kbps
55db...................................4.0km...... .................................4500kbps
60db...................................4.3km...... .................................3200kbps
65db...................................4.7km...... .................................2000kbps

On this chart you see you should be able to get at least 2MB. Which means there is noise on your line preventing the max speed. You could try to reduce noise on your line by either:
Removing the ring wire on your extensions
Installing a filtered master face plate
Rewiring your extension with Cat5e cable or higher

see:

http://www.skyuser.co.uk/forum/cabli...r-results.html
http://www.skyuser.co.uk/forum/cabli...ace-plate.html

Apparently, I'm 2.58km from the exchange, so I'm guessing the attenuation should be a bit better....

I'm going to try conencting directly to the master socket to see what difference that makes.

Also, considering shelling out for the faceplate from aDSLnation. Is this really better than just dangkling off a microfilter ?

[dq1]

Apparently, I'm 2.58km from the exchange, so I'm guessing the attenuation should be a bit better....

I'm going to try conencting directly to the master socket to see what difference that makes.

Also, considering shelling out for the faceplate from aDSLnation. Is this really better than just dangkling off a microfilter ?

For attenuation I doubt it will make a difference. What is does allow is for your telephone extensions to be filtered at the mastersocket, (you connect your telephone extensions to one connector on the back, and if u have ur adsl on another extension you connect that to an unfiltered extension). This means that you don't need filters on the telephone extensions and also it filters the signal at the mastersocket helping to stop noise from interfering with the signal.

If the test socket (behind the master faceplate) doesn't give better results than you get already, it may not be worth it.

[psychocandy]

For attenuation I doubt it will make a difference. What is does allow is for your telephone extensions to be filtered at the mastersocket, (you connect your telephone extensions to one connector on the back, and if u have ur adsl on another extension you connect that to an unfiltered extension). This means that you don't need filters on the telephone extensions and also it filters the signal at the mastersocket helping to stop noise from interfering with the signal.

If the test socket (behind the master faceplate) doesn't give better results than you get already, it may not be worth it.

I think I'll stick me modem in the master socket tonight when I get home and see what happens then....

I've got a laptop as well (connected via wireless) so I can log into the router and see what the stats are like.