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Is it possible to see at different point on a Hlog graph where a peak is at what distance along the copper cabling it is? Why does the Upstream have spikes, and quite steep in one, and the peak at tone 144 621Khz which also creates a large spike on the QLN graph at night?

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Again tonights QLN and Hlog, Also snr tone 144 becomes negative, whereas it is about 8-9db during day? The attenuation according to dmt also states that at that frequency the attenuation is lower?

[burakkucat]

Is it possible to see at different point on a Hlog graph where a peak is at what distance along the copper cabling it is?

Try as I might, I honestly do not understand what it is that you are asking. Could you please rephrase the above question?

An HLog graph is a plot of attenuation (in dB) versus frequency (in Hz).

A QLN graph is a plot of signal power (in dB relative to one mW) versus frequency (in Hz).

Your HLog graph is the first that I have ever seen which shows a "sudden" peak. Very peculiar.    Instinctively I would say that it is indicating a defect in the metallic pathway. Being a peak, it indicates a sudden decrease in attenuation at that particular frequency.

Tone 144 = ((144 x 4.3125) + 2.15625) kHz ~= 623 kHz

Puzzling. 

[les-70]

    When the snrm is small hlog is not measured reliably due to the noise and the trace will show the sort of spikes that you have they echo the noise seen in the qln.  There is no extra information in such hlog spikes extra to the qln.  Smooth dips in hlog can indicate cable faults and the rate of fall off is related to distance from the DSLAM, i.e. the exchange for adsl or adsl2. Your line looks free from such faults with a smooth fall off.

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Is it possible to see at different point on a Hlog graph where a peak is at what distance along the copper cabling it is?

Try as I might, I honestly do not understand what it is that you are asking. Could you please rephrase the above question?

An HLog graph is a plot of attenuation (in dB) versus frequency (in Hz).

A QLN graph is a plot of signal power (in dB relative to one mW) versus frequency (in Hz).

Your HLog graph is the first that I have ever seen which shows a "sudden" peak. Very peculiar.    Instinctively I would say that it is indicating a defect in the metallic pathway. Being a peak, it indicates a sudden decrease in attenuation at that particular frequency.

Tone 144 = ((144 x 4.3125) + 2.15625) kHz ~= 623 kHz

Puzzling. 

I am also puzzled, there must be some reason why the adsl is being affected by all the am interference,  with the spikes on the QLN, perhaps due to a bad joint somewhere,  the reason I was asking about distance was to see if the peak was where the bad joint was, but it would be pointing downwards as a bad joint?

[burakkucat]

In an HLog graph: A sudden increase in attenuation will result in a dip. A sudden decrease in attenuation will result in a peak.

However there is no means of obtaining a measure of distance to the point which gives rise to the sudden attenuation change.

That said, les-70 has given a good explanation for the peculiar result which you have observed.   

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Just ordered an iplate to see if the rf3 filter will help at all, thanks again b*cat!