Need Help Poor SNR
 

Hi friends, please advice me why i am geting slow internet speed. i am curently on virgin 20MB connection. i am only facing this speed issue since last month. since jan 2009 to dec 2009 i was getting 90% good speed.

i dont understand whats going on.
please advice me thanks in advance.

Downstream Lock : Locked
Downstream Channel Id : 38
Downstream Frequency : 451000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 6952 Ksym/sec
Downstream Interleave Depth : taps12Increment17
Downstream Receive Power Level : -1.6 dBmV
Downstream SNR : 28.7 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 47400000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 55.5 dBmV
Upstream Mini-Slot Size :

Boot Code Version : 1.1.2c
Software Version : 2.111.1000
Hardware Version : 1.9

Acquire a Downstream Channel 451000000 Hz Locked

Re: Need Help Poor SNR
 

Your modem is struggling. The SNR at 28.7 dB is below the 30 dB minim,um required for 256QAM modulation; 33 dB is really the required minimum to provide some headroom. There is more noise than signal, put simply. If you need proof, the 55.5 dBmv upstream power level is higher than it should be which indicates impairment/noise to overcome.

First thing to check is that your coax cables are firmly screwed in both ends. Otherwise call it in, providing your modem stats and full EVERNT LOG to the 2nd Line support newsgroup. If you're on Vista/Windows 7, then search the forum on the term "Windows Live Mail" and you'll find instructions on how to set yourself up into the newsgroup; for XP, it's described on the VM web site.

Also, where are you located?

Re: Need Help Poor SNR
 

Thanks mate for ur reply

i live in reading central. what i found infront of my house u kwnow my other end of the cable and telephone wires are just lying down in the road floor. VM they didnt put the cable end propely in the sealed box.

people who walking in the road they walking over it (anybody can easliy remove/unplug my other end with their hands)

really worried. is that effect my speed or snr error?

thanks

Re: Need Help Poor SNR
 

99.99% that this is the cause of the problem. Installers would've put everything into a sealed box on the outside but someone may have deliberately or accidentally knocked it off.

Re: Need Help Poor SNR
 

Agreed. What you found needs fixing. I sugegst you post on the support newsgroup who'll probably get the engineer booked with you today (for another day, of course).

Post your stats, post your story as above. They usually get back to you within 4 hours.

If you're on XP, posting on the newsgroup is described on the VM web site. If you're on Vista/7, the search the forum on "Windows Live Mail" and you'll find instructions.

Keep us posted.

Re: Need Help Poor SNR
 

Hi thanks for ur kind reply N advice finally I logged the cAll with virgin engineer is comming my property tomorrow whn I got the connection last year iam 100% sure thAt they didn't seal the out side cable end with safty box. Please advice me what are the question am I wanted to ask to the engineer? Do I wanted him to changed the cotax cable end or any other sugestion? Thanks again.

Re: Need Help Poor SNR
 

It's the reverse of what's in post #3 that the engineer has to achieve.

You have a result if your SNR is greater than 35 dB.