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[konrado5]

FIG. 7 shows the insertion loss for a loop with length of 4.5 kft. In the absence of a bad splice, shown as plot 702, the insertion loss is small. When a bad splice is present, shown as plot 704 for a bad splice with C=50 pF, the insertion loss increases by a large amount particularly in the lower frequencies. If the average upstream attenuation is measured for the loop with the bad splice, then it is found to correspond to the average upstream attenuation of a very long loop without a bad splice shown as plot 706. Thus, the shape of the attenuation per tone changes significantly when a bad splice exists and results in excessive attenuation in the lower frequencies.

http://www.google.co.in/patents/US20080205501

[konrado5]

Is bad splice HR fault?

[burakkucat]

Is bad splice HR fault?

Yes, it could be. A bad splice (bad joint) can manifest as a high resistance fault (which implies some form of DC connectivity through the joint) or as purely capacitive coupling (no DC connectivity but some degree of AC connectivity).

[konrado5]

But you said me earlier that HR faults are not noticable in Hlog.

[burakkucat]

But you said me earlier that HR faults are not noticable in Hlog.

I have never detected the presence of a high resistance fault from a Hlog plot.

[konrado5]

Are you sure on my line there is not any fault (even slightest)?

[burakkucat]

Am I absolutely sure? No, not 100%.
Am I absolutely certain that I am absolutely sure? No, not 100%.
Is there a possibility? Yes, of course.
So what could be the possibility? Hmm . . . 50% is a nice midway point between "yes" and "no".

What I am trying to emphasise is that it is not a binary situation were the answer is either "true" or "false". It is more like trying to answer the question "How long is a bit of string?"

[konrado5]

drewk has Hlog which is significantly similar to my Hlog.
http://forum.kitz.co.uk/index.php?topic=14704.msg275289#msg275289

[burakkucat]

Yes, the Hlog graph does look similar to your Hlog graph. You both have those shallow undulations.

However it doesn't mean that both circuits are therefore the same. 

[konrado5]

But do you still think my Hlog is not caused by slight HR fault?

[burakkucat]

I really do not know what is causing those gentle undulations in your Hlog plot, just as I do not know what is causing the gentle undulations in drewk's Hlog plot . . . all I can do is agree that they look similar. 

[NewtronStar]

There are three types of HR faults ->

No 1: non service effected (where you may see US errored seconds when phone rings)
No 2: slight effect to service (the SNRm dips when phone rings)
No 3: service effected (no phone no broadband service)

[konrado5]

I have no phone.

[NewtronStar]

I have no phone.

then you will be watching out for No:3 no broadband service that's when the HR fault has become so bad the engineers will be able to track down the fault and repair it and you won't be charged