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69kimbo
23-11-2009, 16:36
Just a quick one to find out what my Downstream and Upstream power levels should be on 10Mbit connection...

After being advised my downstream was too low, and my upstream too high which could have potentially been causing the problems I was having, I took their advice and rung VM.

On reporting my power levels to them, I was told whoever told me those levels were too low/too high was wrong, as apparently my levels were fine.

My Current Downstream:
Downstream Receive Power Level : -12.8 dBmV
Downstream SNR : 34.9 dB

My Current Upstream:
Upstream transmit Power Level : 54.0 dBmV

So my question is... if on here I was told they are too low/too high, but on the phone to VM they say they are fine and no problems, What do you consider the Downstream/Upstream power levels should be (ideally) ?

Mike

xocemp
23-11-2009, 17:19
http://www.cableforum.co.uk/board/12/26006-cable-modem-signal-levels.html

More of a guide than anything else other factors must be considered when looking at RF.

BTW dude, you could have asked this in your existing thread here
http://www.cableforum.co.uk/board/12/33658137-virgin-media-10mb-area-20-brighton.html

And added the contents of
http://www.cableforum.co.uk/board/12/33658382-packet-loss.html

It makes keeping up with you a little more easy ;)

Sephiroth
23-11-2009, 17:37
While the Downstream power level may not be outside DOCSIS spec, there is cause for concern at -8dBmv and at -12.8, it's downright poor. The cause can be anything and is outside your control. The SNR is not ideal although not down to the loss of service threshold. I suspect that number will rise when VM solve whatever's wrong.

Upstream power is not iffy if it is stable.

But your Downstream Power is not acceptable. Can we see the rest of your modem stats and the event log please?

69kimbo
23-11-2009, 18:11
Sure:

Downstream Lock : Locked
Downstream Channel Id : 182
Downstream Frequency : 586750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 6952 Ksym/sec
Downstream Interleave Depth : taps12Increment17
Downstream Receive Power Level : -12.7 dBmV
Downstream SNR : 35.1 dB


Upstream Lock : Locked
Upstream Channel ID : 2
Upstream Frequency : 29200000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 54.0 dBmV
Upstream Mini-Slot Size : 2


Event Log:
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) The s/w filename specified in the config file is the same as ...
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) A software upgrade filename was specified in the config file.
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) Authorized
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) Registration complete!
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) We registered with a DOCSIS 1.0 config file!
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) Received a REG-RSP message from the CMTS...
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) Sending a REG-REQ to the CMTS...
Mon Nov 23 14:58:42 2009 Mon Nov 23 14:58:42 2009 Information (7) CableModem SNMP configure complete
Mon Nov 23 14:58:41 2009 Mon Nov 23 14:58:41 2009 Information (7) IP init completed ok
Mon Nov 23 14:58:41 2009 Mon Nov 23 14:58:41 2009 Information (7) CableModem TFTP init ok
Mon Nov 23 14:58:41 2009 Mon Nov 23 14:58:41 2009 Information (7) CableModem DHCP client init ok
Mon Nov 23 14:58:41 2009 Mon Nov 23 14:58:41 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Information (7) MAP w/initial maintenance region received
Time Not Established Time Not Established Information (7) Downstream sync ok
Time Not Established Time Not Established Information (7) Beginning initial ranging...
Time Not Established Time Not Established Information (7) downstream time sync acquired...
Time Not Established Time Not Established Information (7) Downstream sync ok
Time Not Established Time Not Established Information (7) starting ds time sync acquisition...
Time Not Established Time Not Established Information (7) Locked on the downstream. Waiting for UCDs...
Time Not Established Time Not Established Information (7) Downstream lock ok
Time Not Established Time Not Established Information (7) Sync Start
Mon Nov 23 14:57:26 2009 Mon Nov 23 14:57:26 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) Received Response to Broadcast Maintenance Request, But no Un...
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Mon Nov 23 14:48:24 2009 Mon Nov 23 14:48:24 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Mon Nov 23 14:41:33 2009 Mon Nov 23 14:41:33 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Mon Nov 23 14:06:18 2009 Mon Nov 23 14:06:18 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Mon Nov 23 14:03:00 2009 Mon Nov 23 14:03:00 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.
Time Not Established Time Not Established Critical (3) Received Response to Broadcast Maintenance Request, But no Un...
Time Not Established Time Not Established Critical (3) Started Unicast Maintenance Ranging - No Response received - ...
Time Not Established Time Not Established Critical (3) No Ranging Response received - T3 time-out
Sun Nov 22 22:17:21 2009 Sun Nov 22 22:17:21 2009 Critical (3) DHCP WARNING - Non-critical field invalid in response.

Sephiroth
23-11-2009, 18:34
So let's make this your main thread. That log looks fine apart from the -12.7 downstream power, although the fact that it can't get 16QAM for upstream indicates a difficulty.

So what is your problem? What's going wrong?

69kimbo
23-11-2009, 20:43
It gets Very Very slow at times, and unstable connection disconnecting/modem going idle at least once every hour and 1/2 or so. Was as "okay" as it has ever been since having it upgraded from 2mbit to 10 earlier (8.76mbit) after calling VM and them running tests/resetting the modem settings, but has now back down to the normal (below 1 mbit) I have been getting for the last 4 weeks now. Current speed from www.speedtest.net when plugged direct into modem is:

Ping 228ms
download 0.86mbit
upload 0.1mbit

I don't really want to go though the hassle of having to spend money on the 30+ min phone call to VM again as 1stly they don't listen to your problem, they just seem to tell u everything is working correctly and 2ndly tell me whoever told me the downstream speed was too low is wrong and it is fine...

However, given the download speed, ping, and upload speed, clearly something isn't right despite the fact VM insist everything is working as it is meant to and my router settings/performance is fine apparently...

any ideas

regards

Peter_
23-11-2009, 20:52
I don't really want to go though the hassle of having to spend money on the 30+ min phone call to VM again as 1stly they don't listen to your problem, they just seem to tell u everything is working correctly and 2ndly tell me whoever told me the downstream speed was too low is wrong and it is fine...


Try this

Tech Support via Newsgroups.

virginmedia.support.broadband.cable is the one that you want to use and here is the set up link http://www.virginmedia.com/customers/newsgroups/setting-up-outlook-express-exntl.php

69kimbo
23-11-2009, 21:09
I am using windows 7 which doesn't have Outlook Express. Is there any other way I can do this?

xocemp
23-11-2009, 22:15
Download OE/Windows live or use Thunderbird.

69kimbo
25-11-2009, 21:45
Okay, so how often do virgin check the newsboard as i posted my complaint/problems 2 days ago and still no response to mine or any of the other posts from other people that were posted around the same time. Virgin are really starting to **** me off and am seriously considering leaving not only because of the reliability but also because of the customer service. To be quite frank it is SHOCKING!!

joglynne
25-11-2009, 22:06
Hi Kimbo. Have you actually checked your posting on the newsgroups as some queries that have been answered don't show the normal +box.

Scrolling through the BB support section shows that all enquiries have been answered other than a few made to-day. :shrug:

Ignitionnet
26-11-2009, 00:35
So let's make this your main thread. That log looks fine apart from the -12.7 downstream power, although the fact that it can't get 16QAM for upstream indicates a difficulty.

Nope just indicates that the upstream he locked to is QPSK. Would have shown in the logs if he'd tried to lock to a 16QAM upstream and failed. There are still loads of areas with QPSK upstreams, my own being one of them, the legacy upstreams were still QPSK when I left that and moved to 50M in May.

69kimbo
27-11-2009, 16:31
Hi Kimbo. Have you actually checked your posting on the newsgroups as some queries that have been answered don't show the normal +box.


Yeh it has been 5 days now since my post on there and still havn't had a responce on my post.

any ideas

joglynne
27-11-2009, 16:48
How about just re-posting? It's very unusual for a post on the support groups to go unanswered, there is even an SLA for posts to be answered with in, I think, 4 hours. If that's not the right time limit I am sure a member here will correct me.