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[colchaodemola]

Well guys , at first i was so happy that finally some ISP had started to deliver broadband in my area, but i only get problems during day.
Before put ADSL here , i had no idea about SNR and line attenuation , but after that i started to read some explanations [thank you guys in this forum].
I have a constant problem with low snr between 11am and 5pm and a lot drops in connection , i mean A LOT .
During 5pm-11am i have an almost constant SNR margin = 12 , my attenuation is very high too ~51. While SNR=12 i can sync at 4512/512 but suddenly [not that suddenly anymore since i know almost the right hour that happens]  my snr drops to ~3.9 after 11am and the problems begin. A lot of CRC ERRORS , lose syncs , and related problems, mainly a big throughput loss. I call my ISP and apparently they support staff are dumb, they appear not even know what SNR is :/ , they just keep saying the line is OK , and ask  me if i am not connecting the modem in the computer`s modem port insted the ethernet port [WTF , they really think i can connect a RJ45 in a RJ11 port?? ].
I can not change ISP , `cause they are the only broadband ISP around here.
After read a few topics here  i am thinking in get a netgear DG834 and with some lucky my problems with drops will at least get better. But i have a doubt , sould i take version 1 , 2 or 3 ? Which one is better with low snr  
Thanks.   

[roseway]

Hi, and welcome to the forum.

An attenuation of 51 dB is quite high but should be perfectly usable. However, interference can be a problem, and this is what you seem to be suffering from. If the problem always happens at about 11:00 am then that strongly suggests a serious local source of interference from some machinery which starts up at that time. Do you, or any of your neighbours, have something like that (an exercise treadmill for example)?

You may be able to get an improvement by giving attention to your own wiring and connections - see http://www.kitz.co.uk/adsl/lowSNR.htm for some guidance.

Eric

[colchaodemola]

Now i`ve learned one new english word = "treadmill" , thanks google
Well, i really do not know , i live in in a building / fourth floor , i know my neighboor downstairs does not have one , and the neighboor next door neither.
i tried to look at the page you post , [i have alread looked before], but here in Brazil , telephone plugs are not like that. They are like this:
http://imgproduto.casaevideo.com.br/gif/telefixo/0264504.gif

What about the DG834 ? Will it help ? Which is the best version ?

[roseway]

I'm afraid I don't know anything about the Brazilian system, but the same principles of internal wiring and interference pickup will apply. One of the DG834 series routers might help, as they are notable for their ability to hold sync at low noise margins. However it's quite unusual to have a regular big daytime drop in the noise margin (it usually drops at night for most people) and this definitely points at the probability of local electrical interference. If you can't trace the source of the interference, then you might be able to get an improvement by attention to your internal wiring (if that's permitted where you are) or by trying different ADSL filters.

Eric

[colchaodemola]

Could you recommend a very good adsl filter ?

[roseway]

I don't think I can unfortunately, because the ones which are generally recommended here in the UK are supplied by British companies who don't ship to other countries. But someone else may know better.

Eric

[kitz]

Hi colchaodemola

I dont really have much more to say than what roseway has already said Im afraid.  The same principals would apply for adsl and the way it works, but there may be a few minor differences in equipment at the exchange and the home.

All versions of the Netgear DG834 or DG834G seem to work pretty well.  For a while we continued to recommend versions 1+2 when version 3 was still  new because we werent sure how the different chipset would perform.  However version 3 has so far proved to be just as reliable as the older versions are on longer lines.

The fact that your problems occur during the daytime is also a bit unusual therefore I agree that it would tend to point to something local to your flat causing interference on the line.  Unfortunately this could be many things - central heating pumps can be another favorite... although the list is practically endless :/

From the picture you supplied, none of the filters that we normally recommend would work with the brazilian phone system Im afraid. The UK uses British Telecom connectors, whilst that socket looks like it perhaps takes an RJ-11, ? similar to used in the USA.

[colchaodemola]

Yes , it is RJ11 , Now i have a big doubt, i could not find a DG834 here in brazil , and on ebay.com noone ships to brazil , but on ebay.co.uk there are a few guys that ship to brazil. I know that the power supply is incompatible , but i can built or buy another . But what about the line jack ? Is it RJ11 compatible in the modem ?

[mr_chris]

The line jack for the modem is RJ11 compatible, yes.. and the DG834G is advertised on the Brazilian netgear site (http://br.netgear.com)

Depending on the model you get, you might need to change the Firmware in order for it to work in Brazil, but it should work

[colchaodemola]

hey guys , it there an easy way to force my SNR goes down ? I need to make a test and i need force SNR goes as low as possible. Some way to cause interference , some noise , AM RADIO ?

[colchaodemola]

no ideas?

[roseway]

Sorry I haven't got any bright ideas, unless you can get a router which is compatible with DMT - http://dmt.mhilfe.de/

Eric

[colchaodemola]

Do you know if DG834 v3 works with DMT ?
Well , i am asking cause in DMT page has Netgear DG834GT/DG834NB/DG834PNB , but i think DG834GT has the same chipset DG834v3 , doesn`t it ?

[mr_chris]

I does have the same chipset, yes, but whether it works or not I'm not sure, to be honest - I don't think it does - due to a limitation of the router's command set. The required adslctl command is not available on the v3 so changing SNR target isn't possible.

If you do get a router compatible with the DMT Tool, Kitz has provided a good DMT Tool tutorial here

[colchaodemola]

Hi, finally my dg834 arrived. It was almost 1 month since it was shipped from USA.
Here the status now. I got a DG834v2

before:
Att: 52 , SNR 3.9 , Drops/day ~=150 or more

now:
Att: 46 , SNR 6.1 , Drops/day  = none yesterday / 1 today

i love this modem :p