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lsproc
31-01-2009, 10:02
When downloading large files (i.e. 100mb+) over this 2mbps connection, browsing the internet often cuts off, and the other two computers on the network cant use the connection at all.

The modem is an ntlhome100 connected to a netgear wgr614 which is not qat fault as it has replaced a Belkin router for a different fault.

Signal levels:
Downstream Receive Power Level : 7.29 dBmv
Downstream SNR : 34.62 dB
Upstream Transmit Power Level : 48.00 dBmv
chickendippers
31-01-2009, 10:41
Does it happen when connected directly to the modem?
lsproc
31-01-2009, 10:43
I believe it does, though I havent performed extensive testing as power cycling the modem appears to fix it for a few days.
Stabhappy
31-01-2009, 14:27
Log in to the router every few hours and check if any of the values rise. It would also be interesting to know if any of the power levels change dramatically before you disconnect.
lsproc
31-01-2009, 14:31
The interesting thing is that the download continues fine at good speeds, just everything else is slowed down to the point of timeouts.
Stabhappy
31-01-2009, 14:45
That's somewhat good news and suggests that your power levels may be going out of whack, when it happens take a look and post back :).
lsproc
31-01-2009, 15:16
Righto, ill post back when I haven update.

Ill add I do have an attenuator on the line.

---------- Post added at 15:16 ---------- Previous post was at 14:50 ----------

Update:

Downloading a big update (why is a .net framework SP 250mb...), hasn't cut out yet but the signal level is going closer to 6dBmv, and the SNR is getting close to 50.
Stabhappy
31-01-2009, 15:34
50 downstream snr?
lsproc
31-01-2009, 15:38
Well 49.50

In addition, at one point the modem lost its IP but the download continued, brief loss of web browsing, ill say what the levels return to when the download is finished.

Browsing still working
Stabhappy
31-01-2009, 15:44
that can't be healthy, you'll have to wait for someone a little more clued up about the network to take a look at this - 50 snr is very worrying though IMO, but I can't be 100% sure.
Joxer
31-01-2009, 15:59
50 is fine for SNR - it can'tr actually be too high, its a measure of how much signal there is compared to the amount of noise - higher is better.
lsproc
31-01-2009, 16:16
Download finished, signals stable at post-download levels and everything is fine

Ill post again when I have signals for a case when browsing fails (possibly tomorrow else a few days time)
Stabhappy
31-01-2009, 17:12
50 is fine for SNR - it can'tr actually be too high, its a measure of how much signal there is compared to the amount of noise - higher is better.

ah, goodo.

cheers
Ignitionnet
31-01-2009, 17:47
50dB is very very high for SNR on a cable network, especially considering above it's 34dB. Sounds more like upstream transmit power.

Introducing the attenuator only dropped received power a dB or so, while it increased SNR 16dB, seems unlikely. that dB added on to upstream transmit would have popped it up to near as damnit 50dBmV though.

Hrmm.
lsproc
31-01-2009, 19:26
Suggestions then?

Maybe remove the attenuator?

uhh

This token allows broadbandings to give lsproc a dunce hat! :D

Downstream Receive Power Level : 7.37 dBmv
Downstream SNR : 34.68 dB
Upstream Transmit Power Level : 49.50 dBmv

Silly, silly me :(

Sorry everyone!
Axegrinder
31-01-2009, 19:33
You either have an Ambit 100 or 120 modem (check on the underside of the modem), these are getting quite old, and can start to give up the ghost after a while ;)
Ignitionnet
31-01-2009, 19:35
Here you are sir! :dunce:

Your modem is pretty venerable, might be worth asking for a new one.
lsproc
31-01-2009, 19:37
hehe :D

Thanks for your help everyone!