Kitz Forum

Broadband Related => ADSL Issues => Topic started by: Loading on March 15, 2014, 05:59:59 PM

Title: QLN Graphs
Post by: Loading on March 15, 2014, 05:59:59 PM
The first QLN graph attached is the one from the test socket,and the second is from the master socket with the extensions attached to the rear of the faceplate, why are there such large spikes in the test socket, but not in the master socket, the router and everything else is in the same place, also tested using a 12v battery with all electrical items off (to elliminate rein) and was identical?
Title: Re: QLN Graphs
Post by: burakkucat on March 15, 2014, 06:11:48 PM
. . . why are there such large spikes in the test socket, but not in the master socket, . . .

Large spikes?  ???

In all honesty, within the range of experimental error, both graphs are essentially identical.
Title: Re: QLN Graphs
Post by: Loading on March 15, 2014, 06:31:05 PM
The tones towards tone 255 seem to even out, as they should look, sorry the spikes get worse after 18:00, and becomes unusable. This one attached is as the sun has just set.
Title: Re: QLN Graphs
Post by: NewtronStar on March 15, 2014, 06:46:55 PM
Hi if your loseing tones in the evening then it could point to RFI as being a probable cause, if you could upload a snapshot of tones and select bitloading to see which tones are missing and the relevant radio frequency my be the cause  :-\   
Title: Re: QLN Graphs
Post by: Loading on March 15, 2014, 08:17:04 PM
Yeah it does seem to be rfi but only after it starts to go dark, it must be the line is picking up the interfering stations, rather than rejecting them each spike is a radio station, which can be found using a lw/mw radio, shouldn't the line be preventing these frequencies from affecting the adsl? Also neighbours have crackly lines, mines more of increased background noise, and hissing. I've attached QLN graphs as they get worse. The tones that are unusable are normaly 7-9db, during the day
Title: Re: QLN Graphs
Post by: NewtronStar on March 16, 2014, 03:15:45 AM
I think RFI goes beyone Mr OpenReach's comprehension as when they rolled out Broadband many years ago they should have known that radio frequency interference would impact users on a long lines at some stage or another, once we all have FTTH then RFI will be a thing of the past.
Title: Re: QLN Graphs
Post by: Loading on March 16, 2014, 08:27:23 AM
But it only started to affect after engineering work was done, leaving the line with large number of errors, and a hissing noise after the melodic tones the router makes whilst gaining sync? So there must be some sort of line fault
Title: Re: QLN Graphs
Post by: burakkucat on March 16, 2014, 02:31:16 PM
But it only started to affect after engineering work was done, leaving the line with large number of errors, and a hissing noise after the melodic tones the router makes whilst gaining sync? So there must be some sort of line fault

From what you have just described above, yes, there must be some sort of fault.
I suspect that there is a sub-standard joint somewhere in the circuit. A joint that is possibly showing HR or semi-conducting tendencies. Such a joint will affect the AC balance of the circuit and, thus, make it more susceptible to RFI.   
Title: Re: QLN Graphs
Post by: Loading on March 16, 2014, 02:47:18 PM
Yes and they say well our tests have passed, and that's all we are doing, yeah i have tried in the test socket, and it's exactly the same, the intensity of the hissing and sync tones varies with router.