IDNetters Forums

Technical News & Discussion => Networking & Routers => 2-Wire 2700 => Topic started by: Tacitus on Jul 28, 2011, 19:09:33

Title: Couple of Quick Questions....
Post by: Tacitus on Jul 28, 2011, 19:09:33
1 - Am I correct is thinking the 2700 is Wireless G @ 2.4ghz and doesn't use the 5ghz band?  I've looked and whilst it says that it uses 'G' it doesn't specify the frequency band.

2 - A general point.  What sort of speed variation per 1dB drop(or increase) in SNR is usual?  Eg If I connect at (say) 2560 @ 12dB what sorts of speeds might I expect at (say) 15dB, 9dB and 6dB?

Title: Re: Couple of Quick Questions....
Post by: Steve on Jul 28, 2011, 19:14:49
Your correct with the frequency band, with regard SNR a 3db drop will lose you 5-700k and vice versa.
Title: Re: Couple of Quick Questions....
Post by: Tacitus on Jul 28, 2011, 19:28:31
Quote from: Steve on Jul 28, 2011, 19:14:49
Your correct with the frequency band, with regard SNR a 3db drop will lose you 5-700k and vice versa.

Thanks Steve - thought I was right about 'G' but had no idea about sync speed v SNR ;D

Title: Re: Couple of Quick Questions....
Post by: Lance on Jul 28, 2011, 21:43:44
The sync speed v snr will be specific to your line, but the range indicated by steve is the normal value.
Title: Re: Couple of Quick Questions....
Post by: Tacitus on Jul 29, 2011, 08:19:30
Quote from: Lance on Jul 28, 2011, 21:43:44
The sync speed v snr will be specific to your line, but the range indicated by steve is the normal value.

I imagine it depends to some extent on the levels of noise 'bursts' and how the dreaded DLM interprets them. 

What's happened is that my connection speed has suddenly gone from around the 1600 mark and an SNR of 17/18dB to one of 2560 with an SNR of 12dB.  Presumably somebody at BT playing around, although how long this improvement will last is anybody's guess.  Given the state of the lines through the village I won't be holding my breath.

If the SNR drops to around 9dB, I should be getting the speed I got some 3 years ago when I was with Demon - at least until it all went pear shaped.  It was trying to resolve the problem with their Indian call centre that finally pushed me to iDNet.

To be fair, given BTs attitude, I don't think that iDNet can do much better than Bangalore when it comes to line problems, but at least we understand each other  ;D