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[Bald_Eagle1]

Just for interest, see the attached for an example of a Hlog graph that really shows some physical problems (most probably bridged taps on the internal wiring arrangement).

[GigabitEthernet]

I was under the impression that it wasn't normal for the Hlog to just "fall off a cliff". I'm so very confused

[Bald_Eagle1]

If you could generate or post a recent Plink log I'll have a look at the raw data.

It might be later on today before I can get round to it though.


The attached example from your connection from 14th June definitely doesn't look quite right.

[GigabitEthernet]

Here you are

[GigabitEthernet]

Just had another unexplained resync.

I've had a few of these recently - could this link to the fault?

Edit:

New Hlog:

[Bald_Eagle1]

It looks like attenuation has increased slightly and SNR is now too low to use the U2 band.
(see attached)


Do you still have the Plink log from 14th June that you could post for comparison purposes?

[Bald_Eagle1]

Just had another unexplained resync.

I've had a few of these recently - could this link to the fault?

Quite possibly.

Does SNR/SNRM take a big, sudden hit (or even cause a resync) when dialling out from your landline?

If so, does it suddenly improve when dialling in?

[GigabitEthernet]

Do you still have the Plink log from 14th June that you could post for comparison purposes?

Here is the Plink log from the 14th June at 0900

[burakkucat]

The attached example from your connection from 14th June definitely doesn't look quite right.

I believe that is the plot which prompted me to utter the "falling off a cliff" description.

[GigabitEthernet]

I believe that is the plot which prompted me to utter the "falling off a cliff" description.

Is that still your belief for the newer Hlogs?

[burakkucat]

Is that still your belief for the newer Hlogs?

At a first glance they would cause a concerned second look. But if you refer back to what les-70 has suggested (about there not being sufficient tones with bits loaded for an entire band to be present and used) then they are less disconcerting.

Do look at the lines of Bald_eagle1, Steveh and nstar, they have exactly the same bit loadings as you do as do others with similar sync. I conclude that your cliff edges and bit loadings are normal for your sync.  Those lines also don't show attenuation for the D3 band with no bit loading so your change in attenuation must be just due due to the loss of your tiny bit loading in that band.

[GigabitEthernet]

I did take a look and yes I agree however the question remains: why can those tones not be used?

[Dray]

Because the line attenuation is too high at 90.3 dB

[GigabitEthernet]

But why suddenly is it too high when the previous tones are loading just fine?

[Dray]

It's not suddenly too high, it's rising with frequency.
VDSL Band Status    U0    U1    U2    U3    U4    D1    D2    D3
Line Attenuation(dB):    8.9    42.2    64.6     N/A     N/A    18.0    51.6    90.3