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[sevenlayermuddle]

My DG834GT died the other day.    I've temporarily taken an ST585V7 out of retirement, but I don't really like it much.

On top of that, my line is being particularly problematic at the moment.   I've discovered that I'm getting the odd burst of just a second or so's interference, maybe a few times in an hour, which is occasionally causing the router to reconnect - maybed three or four times a day.  By the time it reconnects the noise has gone, so I don't lose any speed, but there's a risk DLM may take a dislike to it all, and then I'll lose speed.

Before anybody suggests routerstats, it doesn't help much.   It's statistically unlikely for one of it's samples (I think the best it can do is 5 second sampled) to co-incide with the momentary noise burst, so it just draws a nice smooth graph most of the time, oblivious to the problem.

So, I'm after any suggestions for a new router that might (a) have good tolerance of short term noise, and/or (b) provide help in tracing it's source.   The DG834GT was good in the latter respect because the Netgear  html admin gave a screen with a 1 second refresh.  That allowed be to leave an AM radio tuned to various between-station frequencies,  then to look the screen every time I heard any crackles, so to see how the SNR was doing.  I hoped to find out what sort of crackles or buzzes I should be listening for, after which I could maybe home in on the source. I strongly suspect it's coming from a neighour up the road, who's 240V supply lines pass close to my roof, but I can't really accuse him unless I've some means of demonstrating there's a fault.

Sadly, the DG834GT died before any progress was made, and the ST585V7 is proving no help at all.  Also, my line is long-ish (55dB), so I want another router that's OK on long lines (DG834GT and 585V7 both fine in that respect).

[waltergmw]

Hi 7LM,

I've found the 2Wire 2700HGV (AKA BT Business Hub) to be excellent on very poor lines but the downside is that it can be a pest to set up due to the highly defensive firmware locking modifications included at the behest of it's UK provider. However there are good resources available here:-

http://bt2700hgv.tripod.com/ir1002700HGV.htm#The%20BT%20Empire%20Strikes%20Back

I believe Roseway is also using it quite successfully. I have bought several from Amazon-related organisations.

The in-built diagnostics are quite good, but I doubt if they would be too helpful in diagnosisng your noise problem.
You might have a look at the General's blog here and particularly his bit on the WiSpy

http://btbroadbandandhowtosurviveit.blogspot.com/

Kind regards,
Walter

[roseway]

I rather doubt that any other router will stand up to that sort of impulse interference any better than the DG834GT. The 2-Wire 2700HGV may be a bit more resilient, and would be worth trying perhaps. The latest DGTeam firmware for DG834GT includes an option for Impulse Noise Protection (using Broadcom phyR technology) but I don't believe that this works on current UK systems. I'd be delighted to be proved wrong.

Walter posted while I was writing this, but I'll post it anyway

[sevenlayermuddle]

Thanks Walter/Roseway, I'd already been thinking of the BT business hub, thanks to previous mentions on the forum.  I see that it's listed by amazon at £45.99, but if you click on Amazon's 'more buying choices' then it's listed by other marketplace sellers from about £15 upwards, including P&P, which looks quite tempting.   Are these devices all likely to be what they appear to be, or should I beware of buying something that turns out to be subtly different?

That tripod site is a 'Wow', it certainly makes the business hub infinitely more tempting.  From it, I get the impression that the biggest risk of buying on new is that I'd get one with latest BT firmware, which may not be a good thing.  But at £15, I'd be willing to take that risk and, after all, the latest firmware does still seem usable.

I'll also check the General's blogs, but I'm wary of using graphical displays as there's often a time-lag between the noise event and its portrayal on the screen.   But if all else fails, and this should work on any router, I can just leave it on the html stats screen, with a finger on the screen-refresh key, and hit it whenever I hear anything untoward on the radio  to 'test' whether or not the SNRM is being affected.   The trouble with that approach is the age-old issue  of watched pots never boiling.

[roseway]

There are loads of 2700HGVs for sale on Ebay, many of them brand new. That's where I got mine. The vast majority are the current model with the current firmware, and there's no known way of downgrading them as far as I know. That being said, they work very well, and are quite easy to unlock from BT.

[sevenlayermuddle]

I think I shall probably give a 2-wire a try, either off Ebay or Amazon.

My only hesitation, speaking as somebody who never updates any software without good reason, is the vulnerability to force-fed automatic firmware upgrades.   But I can probably live with that risk if the performance benefit justifies it.

Thanks again, 7LM

[waltergmw]

Hi again 7LM,

I've had to struggle a few times with some of the features but in general I agree with Roseway that they can be re-configured.
Note:-

Sometimes a new user-name requires an active broadband connection to fix it in the firmware
Doing a factory reset obliterates all your data and resets back to BT defaults
Earlier versions can be DNS Poisoned to avoid auto-upgrades but not ones that already have V 6 firmware.
Default modem password is now usually the serial number without any alpha final characters

The bit loading picture below is the current from one of my horrors where the BT speedtest provides a miraculous 86 kbps.

Kind regards,
Walter




[attachment deleted by admin]

[sevenlayermuddle]

Thanks again.

It's likely to be after Easter before I can get my hands on one and have time to play with it, but I'll let you know how I get on.  Regardless of my current 'bursts' of interference,  the Netgear & the Thomson are both capable of a worst-case (late night) connection at over 4Mbps, or a best case (mid-morning) of over 5 Mbps,  which isn't bad for a 55/56dB attenuation.   I'll be interested to see if the 2-Wire can do even better. 

Meanwhile, the 585V7, which had been sentenced to life in the loft in response to gross unreliability (lock-ups every few hours), has performed faultlessly for 5 days now - and that's despite having to deal with my intermittent noise problems.     I guess it was a bit cold and miserable in the loft, and it's now on best-behaviour now, hoping it won't get sent back.   

- 7LM

[Azzaka]

You may also find it usefull to turn the UPnP off, as this can cause the modem to reboot.

[sevenlayermuddle]

You may also find it usefull to turn the UPnP off, as this can cause the modem to reboot.

That's always the first thing I do, I regard UPnP as a massive security hole.  But actually, the Thomson continues to be rock-solid so I've not get got around to changing anything.

I still get disconnected up to two or three times a day, but it's obviously just short transient spikes that are causing it as it often reconnects at a much higher speed.    I've never heard any phone noise, and my SNR stays fine right up til the moment of disconnect, and is back to being fine again afterwards.

Thankfully, DLM seems to be leaving my margin alone at 6dB so the disconnects aren't a major problem, I'm hanging onto a respectable IP profile. 

But any suggestions on getting to the bottom of them would be welcomed.  They seem to occur at any time of day or night, there's no pattern.    I strongly suspect the disconnects started about the time  with my neighbours' returned from holiday, and their power lines pass close to my phone lines, but I can't really approach them unless I can demonstrate a problem.  Or I could be entirely wrong, it may be nothing to do with the neighbours.

[jeffbb]

Hi
Have you tried routerstats  . Might get some clues from the SNR marging plots
Regards Jeff

[sevenlayermuddle]

Thanks Jeff, I tried routerstats initially, but it just draws a nice healthy SNR curve, dipping a few dB at night and rising by day, with the occasional (2 or 3 times a day) step change in SNR (and connection speed) which are picked up at the next routerstats sample after the event.

The trouble is, I'm fairly sure I'm just getting momentary bursts of intense interference, there's no warning signs, and certainly no gradual decay of margin prior to losing sync.  And by the time the router reconnects, the interference is over, everything's quiet again, and I reconnect at a perfectly good speed.  I think that's about as much as routerstats can tell me, though.    

A Question for anybody with an opinion on the matter...   As mentioned earlier in this thread, my DG834GT died soon after the problem began, but the 585V7 sees exactly the same disconnects. Should I be worrying about the possibility that the death of the router was no co-incidence, and was related to the interference problem, suggesting maybe mains surges, or nasty voltage spikes on the phone lines?

[waltergmw]

Hi 7LM,

This is a very long shot - Have you tried 17070 Option 1 ringback test whilst monitoring?
(The reason being we've just cured a high resistance fault when BT O  did a lift and shift.)

Kind regards,
Walter

[sevenlayermuddle]

Walter,

I don't hold out high hopes that it's ring-related, mainly as I often get a disconnect in the small hours,  betwixt midnight and awakening at the 7am alarm, and I think I'd notice if the phone had rung.

BUT... it might be more subtle than that, you're right, I ought to try it, it might give a clue.  I'll do so tomorrow when I get back from work, as it's now gone midnight and I wo'nt be popular with the other member of the household for making the phones ring 

- 7LM