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I have a DOWN 'Noise Margin', which I assume is 'SNR', on my router of a normally steady 6dB, but occasionally down to 4 (again this morning for a while) and I am getting the expected rubbish sync. I have a 'long line length' with an attenuation of a steady 48dB DOWN. Interestingly IE seems to deliver better PPRuNe browsing than FF
I have a splitter plate on the NT5. What else can I do to improve the 'SNR'? Would a line change at the exchange help?
you could try asking BT for an i-Plate Thats a faceplate which fits over the master socket and isolates the bell wire (which can act as an antenna and relay noise) Its clutching at straws, but other than get BT to properly check the line theres not a lot you can do - except the usual of change the filters and maybe a new router Which make / model of modem router have you got?
Some routers seem to be more tolerant on noise than others. For instance the BT Business Hubs (branded as 2-Wire) are awful What are you using at present? Also who is your service provider? BT or someone else?
There are tricks you can play on the router Changing the MTU is one. BT used to say that a setting of 1458 was best in the old days of ADSL, but that became irrelevant with ADSL 2 / ADSL+
However it could be worth a try on a noisy line Set the MTU on the router to 1458 and see what happens. You could try pushing it even lower to see what happens, but don't drop below 1400 There used to be a BT script file available for download which would also set the MTU of the network port of the PC to 1458 (so that all balanced) but I've not seen it for a while. I no longer have a copy (it dated from Win98 days...)
There used to be a BT script file available for download which would also set the MTU of the network port of the PC to 1458 (so that all balanced) but I've not seen it for a while. I no longer have a copy (it dated from Win98 days...)
You need a script from BT to change the MTU of your PC milo ?
Are you on a fixed line speed ? At that attenuation 6db should give you 4000 down load plus. Presume you have tried the test socket. On the variable adslmax system the download speed will adjust to a level which gives 6db (normally) which will then trail down a bit after dark as am radio interference kicks in. So its the download speed which is the variable not the SNR. On wiring, its transmission line theory and you don't watch an impedance mismath anywhere on your wiring ( ie no tee junctions). The I Plate is only the same as cutting the orange ring wire anyway. Tried the solwise and adslnation sites ?
Incidentally, altering the mtu is unlikely to help (your isp will advise optimum setting) but if you are not on AOL then 1500 is fine. Also the BT business hubs I have found to be good on my line (51db attenuation) holding on to below 3db snr. You can pick them up cheap on ebay and then unlock them (single ssid version much prefered). Different routers report differing attenuations, BT hub says 51 db for me, dlink said 55 db.+ For comparison, I get between 3800 and 4300 -ish download syncs at 6db snr but with the odd overnight retrains.
Router into the ADSL socket on a splitter plate. My ISP tells me (he had never heard of an ADSL splitter plate or an I-Plate!) that I still have to plug into the master socket direct to check to see if the CRC errors can be reduced.
I thought the ADSL socket WAS direct to the master but he sounded very confused! Maybe I am!
If you have a modern face plate, the bottom bit pulls out. In doing so you also take all the other bits of kit out with it so it isolates the input line from the rest of your wiring and appliances. Think it is called an NES 5 socket or something (which you may or may not have). The I Plate is just a way of isolating the 'third' (orange) wire, which isn't needed these days and can unbalance the signal lines and make them more susceptible to noise - but only as induced on the internal wiring. So first thing is to see what the 'raw' signal is like and to see if it differs markedly from what you see normally. If so there is scope to improve your internal wiring.
2) Knows what a splitter plate/I-Plate is (they call it an SSFP)
3) Has English as his native tongue.
A phone line test indicates a 'possible' line problem. We are monitoring overnight with the phones unplugged, and a filter on the router line into the MS - and he has promised to schedule a call tomorrow!
Looking at eliminating the router as a problem since the phone wiring seems to be 'innocent' and it might just be that I have a faulty 'SSFP'.
Bizarrely a test into the master socket (which should not be necessary with the 'SSFP') whacked my speed up from 3.8 to 4.9 and while giving me far less errors, they were still too high.
Not sure I understand what a 'splitter' is. The I Plate is an additional piece of kit which I think you have to buy from BT. I have a NES 5 faceplate but no 'I Plate' as I simply didn't connect the orange wire : achieves the same thing. The better result from the test socket points to room for improvement in your internal arrangements (telephone circuitry, not the wife). Not sure how you know what level of errors is ok. I don't here, and one set of 'errors' (FES or some such thing) is purely because the line is interleaved and not 'fast'.
Incidentally, if you are on windows vista or later, all the web gossip seems to indicate that windows now does a fine job optimising settings (so no more Drtcp and similar tweaking tools). Unless your ISP says otherwise, I would set the router to mtu=1500 and leave windows alone.
Mr O - the 'splitter' or SSFP or I-Plate does, I believe, do a bit more than you think ie it filters the phone socket at the NTE5 (ie 'splits') as well as isolating wire 3.
Anyway, things have moved on - internal wiring checks out fine - no difference in errors or speeds connected or not so the next step is to try another filter and find a mate with a spare ADSL router to swap out BEFORE I call BT out to find it is my router, and pay them the odd £100 for the fun of it.
Question, even at my lowish speeds would this help throughput as it's 10/100/1000 compared to the present 7 yr old 10/100 type?? It would be used primarily for a hard wired [cat6] connection to a sat receiver and a secondary [but don't tell them that ] home network.