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Standard User AvengerUK
(member) Wed 21-Jul-10 17:57:16
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Router to hold sync with Noise Bursts?


[link to this post]
 
Hey all,

Ive recently had a new (second) line installed - which has been running on a DG834G V5 - which I bought as my old router (v3) kept sync on the other line well - however, My line for one reason or another has large noise spikes occur, (15db --> 0db) - this happens on both lines, however one keep's sync 99% of the time, the other does not.

I'm currently testing my older DG834 on the new line to see if it hold's sync better than the newer one - however, I'm interested to know that should the older router keep sync better than the newer - as to if there are any other router's known to hold sync as well / or better?


Thanks!
Standard User b4dger
(fountain of knowledge) Wed 21-Jul-10 18:23:27
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Re: Router to hold sync with Noise Bursts?


[re: AvengerUK] [link to this post]
 
My line is much more stable with a Broadcom based router. See link in my signature for details.

Your Netgear v3 and v5 both use different chipsets - but neither of them Broadcom frown

It might be useful if your post your line stats.

-------------------------------------------
Freeola[EntaNet] Faraday IPSC node
Hmmm... Understanding ADSL | Map Coordinates | and more...
SNR: Netgear DG834>2Wire 2700>Thomson ST585v6 My Router Experience
Standard User AvengerUK
(member) Wed 21-Jul-10 20:21:24
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Re: Router to hold sync with Noise Bursts?


[re: b4dger] [link to this post]
 
Line stats at the moment are:

ADSL Link Downstream Upstream
Connection Speed 3712 kbps 448 kbps
Line Attenuation 52 db 14.5 db
Noise Margin 12 db 19 db

So far this V3 seems much more stable than a V5!


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Standard User RobertoS
(legend) Wed 21-Jul-10 23:12:59
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Re: Router to hold sync with Noise Bursts?


[re: AvengerUK] [link to this post]
 
v3 is a TI AR7 chipset. v5 is Conexant.

It is possible the DSLAM/MSAN at the exchange is more comfortable with the TI.

Your noise margin is very high. Possibly due to the instability you have described causing it to be raised. The norm is 6dB. That is costing you a lot of speed. On 52dB attenuation I would expect well over 5Mbps connection speed, possibly 6Mbps. Odd that the upstream attenuation is so low as well - I would expect mid-20s with a 52dB downstream.

I think we need to look for the cause of the noise bursts rather than worry about what kit is to be preferred.

For starters, have a read of the Troubleshooting pages on my website. See if anything fits you.

My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost. Internet connection - O2 Standard.
Standard User AvengerUK
(member) Wed 21-Jul-10 23:34:03
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Re: Router to hold sync with Noise Bursts?


[re: RobertoS] [link to this post]
 
our other line, (same cable - just that's on the v3) syncs at around 5500 with a noise margin set at 15db strangely with similar line stats to my own - however having run routerstats on this, its clear the noise bursts are still present, but does not disconnect the line.

I've already looked to see if there is a ringwire (there is not) - checked the filter, used the test socket - checked any electrical equipment (nothing seems to effect it) around - we also raised it with our ISP - however predictably BT said there was nothing wrong (and having a engineer would only end up with us having to pay the charge) - I'm actually taking a look at the V4 of the router, which uses a broadcom chipset. The TI compared to the Conexant is definately much more stable!
Standard User Tacitus
(experienced) Thu 22-Jul-10 10:44:35
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Re: Router to hold sync with Noise Bursts?


[re: AvengerUK] [link to this post]
 
In reply to a post by AvengerUK:
....The TI compared to the Conexant is definately much more stable!
I used to have a Draytek (Connexant) which started flapping when my line had a bout of instability. I switched to an AR7 based router and the problems disappeared.

For some reason the AR7 seems to have a bad name but I think the results you get depends on the state of the line being used and, probably the firmware. The AR7 seems to trade speed for stability, so in general you will probably get a lower sync.

Of the major manufacturers I believe Zyxel are mainly AR7 based.
Standard User RobertoS
(legend) Thu 22-Jul-10 19:46:21
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Re: Router to hold sync with Noise Bursts?


[re: Tacitus] [link to this post]
 
I think most of the bad news about the AR7 is when it is used on an O2/Be LLU connection. It and the Be DSLAMs are not good friends. Most other reports I see of it are favourable, as per the OP here.

Conexant in general - I have yet to see anyone praising them.

@AvengerUK - The fact your two lines each use one pair of your cable is only relevant as far as the telegraph pole if you have one, and certainly only as far as the street cabinet. From there connections can take wildly different routes.

However if the same noise bursts are present on both, and if the attenuations are similar, they probably take similar routes.

My broadband basic info/help site - www.robertos.me.uk
My domains,website and mail hosting - Tsohost. Internet connection - O2 Standard.
Standard User b4dger
(fountain of knowledge) Fri 23-Jul-10 08:34:35
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Re: Router to hold sync with Noise Bursts?


[re: RobertoS] [link to this post]
 
The TI AR7 is a complete loss on my line - 51db attenuation and normal BT (with a TI DSLAM).
Changing to a Broadcom based router transformed things for me.

See the link in my signature for details.

-------------------------------------------
Freeola[EntaNet] Faraday IPSC node
Hmmm... Understanding ADSL | Map Coordinates | and more...
SNR: Netgear DG834>2Wire 2700>Thomson ST585v6 My Router Experience
Standard User Tacitus
(experienced) Fri 23-Jul-10 10:12:33
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Re: Router to hold sync with Noise Bursts?


[re: b4dger] [link to this post]
 
Shows how much of a lottery mixed with a Black Art, Broadband is smile

I've used AR7s on both my line and my sisters, each on a different exchange. Mine is a poor line which on a good day will just about sync at 2M and stay up all day unless it rains, whilst my sister's line will sync consistently around the 6M mark and stay up for two weeks or more come hell or high water.

I've also used a 2-Wire on my line which despite its reputation for rock solid stability, is at best no more stable than the AR7 and, at worst less so.

Like many people I've acquired a shed full of modems of different varieties as I've tried to wring good results out of a poor line. smile
Standard User AvengerUK
(member) Sat 24-Jul-10 15:05:41
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Re: Router to hold sync with Noise Bursts?


[re: b4dger] [link to this post]
 
Attached a DG834 v4 this morning - (broadcom chipset)

So far, so good - I dont recognise the graph.

Been up for around 4 hours so far, wont be sure until its evening (when most D/Cs occured) - but rather than 15db to 0db spikes, its not dropped below ~11db for a spike so far!
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