Intermittent Connection : T3 time-out

[GrahamP]

Hi. Apologies if this has been covered elsewhere

For the past 5 or 6 weeks I have been suffering from an extremely annoying intermittent connection. My modem is downstairs and I am hardwired upstairs so I don't always get to see the modem, but:

The ready light on my modem stays steady
as does the ethernet and sync lights. The send receive lights seem to go blank however and it usually takes about 5 to 10 minutes for the modem to recover.

This is not good if your are using your connection through a Router as it seems to excercabate the connection issue.

I recently had my modem replaced to the 256 model but the problem remains.

My connection comes through the wall and is split into TV/Modem. I'm currently using the connection directly from the wall (not split), but it still keeps happening.

I'm having an engineer come tomorrow so I would like to be able to suggest some solutions.

My modem diagnostic/power levels seem fine:

Downstream Lock : Locked
Downstream Channel Id : 0
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 : 39.8 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 25584000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 39.3 dBmV
Upstream Mini-Slot Size : 2

But my event log tells a different story:

I won't post the entire log but the main messages include:
Critical (3) Started Unicast Maintenance Ranging - No Response received -
Information (7) CableModem software upgrade failed
Notice (6) SW Download INIT - Via Config file cmreg-ntlhm250-mid.cm

Can someone help with some ideas please? This is extremely disruptive when working from home, or gaming!

Many Thanks in advance

[sstainer]

would'nt worry to much about the log i got those exact messages and all is fine

Your power levels look ok but read below.

Be careful of reading modem logs, because what happens when you reboot your modem is that every single update for that modem is received at the same time giving you those worrying logs.

My modem is a Motorola and if I look in my logs I will find some with the Date stamp of 1970 and we did not have broadband then.

[GrahamP]

Hey. Thanks for the quick responses

That makes it even more concerning as I don't have an obvious solution to the problem!

I'm still getting an intermittent connection issue. For instance, if keep cmd open so that I can ping www.ntlworld.com whenever things start going ary, e.g. I'm dropped from Conan and Skype, during this time, I lose on average 50% to 75% of packets. This might go on for 10, 15 even 20 minutes until it resolves itself.

This is also extremely frustrating as I work from home through a fire pass. If my connection is interupted, the whole session shuts down, work, emails everything!

Can you think of anything else I can ask the engineer to look at?

[eth01]

"Notice (6) SW Download INIT - Via Config file cmreg-ntlhm250-mid.cm" this is just your CM pulling config from TFTP. i'd go onto newsgroups, to see what they could do

[GrahamP]

... It just hung again in mid response!

From what I can see on other newsgroups this update issue (Notice 6) doesn't seem to be a problem.

I'm more concerned about the T3, Ranging No Response log. Also, when I phoned up, they said my modem had reset itself around 70 times within the past few days.

Btw, I'm using a brand new Router, NETGEAR, and am wired. The problem also occurs (although not quite as much) when connecting directly to the modem.

[GrahamP]

Hi All

I just looked at the modem diagnostic during my connection dropping experience.

Downstream Lock : Not Locked
Downstream Channel Id : 0
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 9.5 dBmV
Downstream SNR : 39.4 dB

It seems that when my Downstream Receive Power Level goes above 9.3 dBmV my modem has difficulty keeping a download lock.

Can this be easily fixed?

[Axegrinder]

Those power levels are within limits, the the D/S power level goes over 15dbvm thats when you should start having probs, what about the upstream power?

[GrahamP]

I've just put a dimmer between the main line and the (tv/cable) splitter. My Downstream power is now between 3.5 and 4.5 dBmV and things seem to be working 100%

Will Virgin get the arse if I tell them to cancel the engineer?

[jaycee]

They shouldnt do... the engineer wouldve just installed the same attenuator you have!