New modem, keeps dropping connection

[jillyd72]

Bit of a newbie here, I have had virgin broadband for years and very few problems. I have a linksys wireless-G router which is direct into my desktop pc and then we have anything up to 3 laptops running from it.

Recently we have been 'upgraded' to virgins new 10mb service and I have a new modem from them which is the ambit 256. This is when my probems started. My connection is fine for a while, then suddenly everyone will lose connection and although the lights on the modem are green, we cannot connect without doing the 30 second reboot. This is becoming a several times a day routine. Strangely it seems to be sparked off by someone else on the network logging on or moving files etc. Then it will be absolutely fine again.

I suspect it's settings rather than hardware but am at a bit of a loss where to start!

Any suggestions gratefully recieved.

Jilly

[vinh1000]

post your power levels and let 'Moldova ;) ' see

[joglynne]

Hi Jilly and welcome to the forums.

In case you haven't been able to work out how to get the details vinh1000 mentions you need to browse to http://192.168.100.1/ and if asked to LOGIN the username and password are both root.

Copy the details shown on the pages shown on the left of your screen as UPSTREAM and DOWNSTREAM and post them here so that one of our more knowledgeable members can have a look at them. Moldova is away for a few days but there are other members who will look to see if they are OK :)

Do not post your IP or MAC details and ignore all the scary things in the Event Log as most of them will be totally irrelevant to your modem.

[jillyd72]

Thanks jo for your comprehensive reply.

Downstream Lock : Locked
Downstream Channel Id : 2
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : -8.0 dBmV
Downstream SNR : 38.2 dB

Upstream Lock : Locked
Upstream Channel ID : 2
Upstream Frequency : 29200000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 49.0 dBmV
Upstream Mini-Slot Size : 2

Today I have done a hard reset of my router and flashed it with the latest firmware. Also it seems logical it isn't the router as I can still view the network devices (router and other pcs, wired and wireless) when the internet goes down.

Thanks in advance

Jilly

[fatassmichael]

your downstream power is a tad too low

[joglynne]

Can someone help here and say whether the Downstream Receive Power Level of -8.0 dBmV is the cause of Jilly's problems and whether it is bad enough for her to need an engineers visit?

[Tuvete]

sorry to hijack the forum but i have exactly the same problem and setup.

Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 0
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : -1.2 dBmV
Downstream SNR : 39.5 dB

Cable Modem Upstream
Upstream Lock : Locked
Upstream Channel ID : 1
Upstream Frequency : 18800000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 52.5 dBmV
Upstream Mini-Slot Size :

[roger_chef]

jillyd72, if i were you i would login to the vm newsgroups and get an engineer out. If you dont want to use newsgroups then ring techy support, i think others say best just after 8am so you get someone from england?

[Feenix]

jillyd72, both of those power levels are in spec.

[musicbravo]

jillyd72, both of those power levels are in spec.

Agreed, my d/l signal is sometimes down to -9.8dBmV and is still within spec

[raybo62]

You can go into your router settings and change the frequency its set at normally routers are set at between 1-5 but you can change it to anything upto 13 then reboot everything and see what happens

---------- Post added at 10:01 ---------- Previous post was at 09:58 ----------

Can someone help here and say whether the Downstream Receive Power Level of -8.0 dBmV is the cause of Jilly's problems and whether it is bad enough for her to need an engineers visit?

-8 is a bit low is there an attenuator on the back of the modem if there is take it off see if it improves it

[musicbravo]

-8 is a bit low

For the ambit 256 -8dBmV is well within spec according most techs

[Zhadnost]

I'd have thought that -8dBmV is within spec for QAM64 but borderline for QAM256.

And since these figures drift, it is probably going out of spec. the best bet is to post them on the support newsgroup, where an expert will give you a proper answer.

As far as Tuvete is concerned, The upstream Transmit power is too high, should also probably leave a note on the support groups.
(http://www.cableforum.co.uk/board/members/61772.html)

[VMboy]

For the ambit 256 -8dBmV is well within spec according most techs

So I take it I have a major problem.

Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 4
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 10.6 dBmV
Downstream SNR : 38.6 dB

[Sephiroth]

So I take it I have a major problem.

Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 4
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 10.6 dBmV
Downstream SNR : 38.6 dB

See my response in your own thread.