Fitting Filters

[#1]

maranello,
Your second set of readings is worth chasing.
You may enjoy a read through me web site and a look at my spectrograms at:
http://www.dougrice.plus.com/Erlangs/adsl_Appendix.htm#l19
On the right is the downstream/upstream speeds and time stamps. Sorting out extension wiring can make a vast improvement.
best wishes, Doug

[#2]

Thanks for all the advice from contributors to this thread. I think I'm getting a better understanding of how ADSL broadband is supposed to work.
I have been running for nearly a week now with the router and one phone connected via a single filter to the test socket behind the master. The performance of my connection over this period has been variable to say the least.
The good news. My IP profile has improved up to 1500kbps, although I have not seen much improvement in throughput (450kbps max) from the BT speedtester.
The bad news. Last night's results were poor, profile (BT) has dropped to 350kbps and throughput was only 82kbps!! I have also on at least one occasion had difficulty getting synchronisation. IP profile (Plusnet) reduced to 500kbps.
Whilst I haven't eliminated the house extension wiring as a cause of interference, there is clearly some other cause of the unreliable connection. The possible culprits are either
1  my phone
2  the filter
3  the router
4  the phone line
The phone is a cordless DECT handset whose base station is connected to the same filter as the router. As this is filtered, I am assuming that this should be sufficient to isolate any potential phone problems.
The filter was supplied by PN and has been in use for only four months. I have a second filter I could try in its place, to see if this makes a difference.
The router is a Voyager 210, again has only been in use for four months. I tend to turn it off when not in use.
I have not tinkered with the phone line at all. The speedtest results calculate the line attenuation at 63dB, and from the information I have seen the best I should expect is ~500kbps. This seems at odds with the increase in IP profile that has occurred over the past week, since I can only assume that this has been driven by resyncs above 500kbps. Is it the case that the increases in speed have made the line more unstable and prone to disconnections, and that this is a different situation to that which existed before I connected to the test socket?
I emphasise again, I would be perfectly happy with 'only 500kbps' provided it would be more reliable.
I just remembered that my neighbours across the road were using an angle grinder yesterday evening. Even though my router was powered down during this period, could this be a source of interference which would cause a 'sync blip'? Can Plusnet tell me how many such events have occured over the past week?

[#3]

Hi again Maranello.
With 63dB attenuation you can expect something approaching 2mbps sync speed "at best" and an IP profile of maybe 1500. Sounds like that was achieved for a while.
So, as you suspect, something is causing variations, the question is what?
Your profile, once it drops, stays down for a while. However your router sync speed will normally recover quite quickly (unless the SNR Margin has been increased too).
So the thing to keep a log of is the sync speed and SNR margin as noted by your router - and attenuation if it changes! Then just see if a pattern emerges.
It 's worth double-filtering the DECT phone as they can be problematic. Obviously the router goes into the filter closest to the socket or it just won't work!

[#4]

Maranello,
After I sorted out my wiring and rebooted the modem and the profile sorted itself out, the forum suggested RWIN tweaking.
My downloads speeds were improved by the use of TCPoptimizer from http://www.speedguide.net/
My portable went from 1500 to over 4000 kbs. It needs a reboot to restart the TCP/IP stack.
The wiring trashed my Download speed and after sorting it, my down stream speed is now a staggering 7136 kbps!
Best wishes, Doug

[#5]

Here's an update, for future reference.
I have acquired an additional in-line filter, which means that I can (and have) double filtered my DECT phone and also have a phone plugged in upstairs with an additional filter. I was running for a while with the upstairs phone disconnected, the DECT double filtered, and router single filtered to the test socket, but I found that I was still getting interruptions, difficulty re-connecting and variable download speeds and profile. I suspect that directly connecting to test socket may not have been maintaining a reliable contact as the retaining clip doesn't work in the test socket.
Now I have securely screwed back the lower faceplate of the master socket, firstly removing the orange wire from the terminal labelled 3 (the bell wire), and the sync rate has immediately increased from ~430 to ~1000 kbps. It also seems that BT were reasonably quick to increase my profile from 350kbps to 1000kbps, and now it seems that PN have increased it at their end from 500 to 1000kbps.
I will continue to monitor the connection, but have so far resisted placing the order for an ADSLnation filtered faceplate. Filter failure seems to be frequently considered on this forum to be a potential cause of connection or speed problems, and if this happens it would be much easier (and cheaper) to replace a plug-in filter rather than a faceplace filter.
Thanks to everyone who contributed to this thread, the advice is much appreciated and will hopefully be of help to others with similar experience to mine.

[#6]

Have you been using the pulse dial phone while your broadband is connected? 
It may not be the cause of your problems but pulse dialling by its nature produces wideband impulse noise which could affect your ADSL signal.  Theoretically a good microfilter should prevent this from affecting your ADSL signal but it will depend on the quality of the filter.  It may be worth trying a tone dial phone instead (or looking to see if there's a switch on the phone to change it to tone). 

[#7]

The pulse dial phone is rarely (if ever) used for outgoing calls, it's plugged into an upstairs extension to save running downstairs to answer the cordless phone when it's sat on the charger. The last time it was used for outgoing call was to report a power failure (cordless doesn't work). I have three of the in-line BT filters supplied by Plusnet with my router, I'm assuming that these are of good enough quality, and once labelled up I can swap out each in turn to see if this makes any difference.
I do have a tone dial corded handset up in the loft (apparently, its not the right colour for the room), which I can use for quiet line testing.

[#8]

If your pulse dial phone has an 'old' bell set in it then even via a filter it could upset things if its bell impedance is the old 1000 ohm instead of 4000 ohm but even this may upset things. Try syncing without the phone plugged in and see what happens after its plugged in. Dialing pulse ought not to affect things except on a marginal line. Ringing current is a more stringent test of things!
If those filters have BT on them and came with your 210 router, they are high quality filters and you should have no problem with them except maybe with that old phone. By the way that 15.5dB attenuation figure is a known bug which occasionally manifests itself on the 210 router.

[#9]

I can confirm that the quiet line test doesn't work with pulse dial phones.
All three filters in use have the BT label, two came with my 210, the third came with another 210 that my referree received and does not need to use.
Could only try two tests this weekend (long story, best forgotten once the pain and bruises subside!)
With router stats displayed, made a call from mobile to home number, pulse phone connected to extension. Noise margin reduced from 12.1 to 11.9, but I have seen this fluctuation in normal conditions so not significant. In any event, the bell wire is disconnected so I'm not that surprised that nothing much happened.
Having gained access to the master socket (involving moving heavy furniture), for some reason when connecting to the test socket my sync rate dropped from ~838kbps to 256kbps.  Not the result I expected!
Since then put master socket frontplate back and have been synching at around 1200+kbps, although with a minor glitch yesterday at around 5-6pm when lost connection a couple of times.

[#10]

Update
I have been getting reasonably consistent sync rates of ~1000-1200kbps over the past two weeks. During this time I have only had the router powered up for a couple of hours daily, except for couple of days when I was away from home). Last night I left router on overnight and this morning the sync rate had dropped to 256kbps. Router stats also reported line count of 3, which I guess means that the router lost sync twice since the up time was reported as only 3 hours instead of the expected 10. This has been noticed before from logs provided by Plusnet.
So my question is this. What could be causing these resyncs, which are occurring in the early hours of the morning when there is likely to be very little activity on my line?

[#11]

Hmm. You haven't got any intermittent crackling noises on your phone line have you?
If you're a BT line rental customer dial 151 and use the autotest in case that picks up something. If you're a PN phone customer, ask them to run a line test for you and post back the results.
Regards,
Chris.

[#12]

Thanks for the advice, Chris.
My home phone provider is the Post Office! I intend to try the quiet line test in the test socket behind the master socket, once I can get hold of a tone dial corded phone. I only have a pulse dial corded and a cordless phone conveniently available atm.
I'm not sure whether to consider myself fortunate that the resyncs are infrequent, or if by limiting the time my router is powered up I am masking the problem. I am reasonably confident that I have eliminated filtering as a cause, just the router to check before considering potential external sources.

[#13]

Quote from: maranello

Now I'm confused. Also, from other threads I have read the bell wire is stated as being on terminal 3, so for the extensions to only need terminals 2 to 5 connected how can this be correct. Also, if I plug into the test socket or master socket then the bell wire will still be connected, unless I tamper with the line in which I'm not supposed to do.

Hi there; Just a few points that may help you .
You only need a bell wire if you have more than one old style extension phone. The wire is to help the solenoid in the old bell phone ring  the phone. So for most of the time it can be left disconnected. If connected it acts as an antenna picking up any old rubbish round the house. If the phone cables run past a microwave you can forget ADSL. The house being recent probably has more of a bearing on extension faults, especially if BT didn't fit them. I've had to abandon internal extension wiring in several newish homes because the extension wiring  wouldn't allow an ADSL signal through even though the phones worked fine.
You don't need more than one filter on one phone or router outlet The ADSL side isn't filtered anyway, it connect s direct to the copper pair on terminals 2 & 5. The phone side is filtered so as to prevent interference from the ADSL signal making the phone difficult to hear. However a phone & ADSL link  will often work ok without a filter except when the phone is picked up to answer or make a call as a surge goes down the line. The modem/router then has to resync the ADSL link. Adding another filter will make no difference to your phone or ADSL unless you plug  the router into the second filter which will have no ADSL signal on it!
Finally I would leave the router on 24/7 so as to allow the gear at the exchange the chance to satabilise the ADSL connection.
try the Solwise site for good faceplate filters; what you need is an NTE5 filtered faceplate on the master socket. Then you can connect to the back of the new faceplate filtered and unfiltered  extension pairs  to wherever you like in the house and fit the appropriate sockets for either phone or router wherever you want them. Thats what I do in problem settings. this  solution is neat and tidy ad avoids the use of unsightly dingly dangly filters which can get knocked and cease to work properly. What is more all this is perfectly legal to so as long as you don't disturb the incoming cables connected to the rear of the master socket.
Best of luck
Graham

[#14]

Quote from: gpsmout

You only need a bell wire if you have more than one old style extension phone. The wire is to help the solenoid in the old bell phone ring  the phone.

Also, most modern primary faceplates contain a capacitor to replace the function of the bell wire. ADSL Filters also contain a capacitor to do the same.
The situations where it would be needed are very very rare these days. (No filter, old phone, old faceplate)
Most people can remove it and forget all about it.

[#15]

Thanks Guys, advice always appreciated.
Graham, your point about non-BT installed extension wiring is not something I have previously considered important, although on reflection maybe I should. I have disconnected the bell wire from the master socket faceplate, but not touched the extensions. I know that the same people who installed the extension wiring also installed wiring for an alarm system. When I subsequently tried to install an alarm system there were a few problems, and I had to ignore some of the wired locations. Noticed that some of the (alarm) wiring both in the loft and underfloor was stretched quite tightly, wouldn't be surprised if the phone wiring is the same (in fact, wouldn't be surprised if the two systems were interconnected in some way! As for the plumbing...!!!).
Just about to order the ADSLnation filtered faceplate. For the price of a good quality in-line filter (£13.50 incl p+p) but with better functionality and to eliminate the internal wiring as a source of interference, this sounds like money well spent.
Had another resync when leaving router on overnight last night, which bumped sync rate down from ~860kbps to 286kbps (why is it always an even number?), so I am reluctant to leave router on 24/7. Double filtering the DECT phone does appear to make a small difference to the reliability of my connection, I appreciate the explanation why this should have no effect but certainly not causing any harm at the moment and others have also suggested this could help.