First failure for a month, line problems, disgusted with Plusnet telephone support

[#1]

As the faceplate is in essence a low pass filter, I would think that the anti-REIN component(s) would have to be on the DSL side to have any effect.

[#2]

That is exactly what I was thinking. A standard filter is just a low-pass for the phone side were as the DSL side remains unfiltered.

Given that REIN is random and could be anywhere in the frequency spectrum, I don't quite understand how a filter can determine what is signal and what is noise and reject just the latter.

[#3]

...and therefore REIN picked up on the phone side would not reach the DSL side. QED. 

[#4]

But REIN picked up on the inbound line remains unaffected?

[#5]

Not my area of expertise, but as I understand it the anti-REIN bit of the SSFP is designed to help with REIN, but is not a silver bullet, and in some cases will not be efficacious at all.

Only just seen your edit in Message 17, and I'm afraid I haven't a clue.

Hopefully someone will be along soon to tell us.

[#6]

Hello everybody, thank you for all your useful comments and discussion Firstly I can confirm the new master socket is a 5C. All the extension (3) wiring terminates there in star fashion each with a filter on its outlet. The modem is plugged into the 5C via a filter. I have been wracking my brains how to get rid of the bridge taps (insofar as ADSL is concerned) without upsetting the 5C install and my solution is to remove the fixed extension wiring from within the 5C, terminating them instead immediately behind it (physically) and connecting to a short length of flexi with a BT phone plug crimped on the end. This flexi will then exit the 5C housing and plug into the modems filter hence all the extension wiring is filtered rather than being connected directly across the AB incoming pair. This I hope will improve the SNR marginally enabling the modem to be better able to deal with REIN.

Looks like these Mk4 faceplates with VDSL filter potentially have four common mode chokes and a ring line inductor, or maybe just 4 line inductors, not possible to tell from picture, would be interesting to find a schematic). The ones I use (NE5000) have one cm stage plus 4 discreet inductors (2/line) and have so far of all those I have tested the best performance.

I used to have a DECT phone many years ago in a different house and it stuffed the broadband badly, not something I would willingly have in my house again! Guess I could have just had a bad one......

I had not heard of this anti-REIN faceplate, but like the Mk4 going by your comments your not really sure where the filter is, another case for some schematics that will probably never be forthcoming

I will post some plots in a minute, all quiet so far this morning, I mostly watch snr and fecs (the latter being a little more sensitive).

Sorry if I have missed any points and thank you all again.

[#7]

I finally got around to rewiring the extensions so they are filtered at the 5C master socket this morning (A+B only, no ring wiring)..

For anybody interested I enclose pictures of the NE5000 filter that I use, they used to be supplied with speedtouch modems years ago.

I knew it was not a good time to restart the link before I started as the snr was lowish, what was interesting was the QLN plot (enclosed) on restart that shows a huge amount of high frequency interference. I keep thinking of VDSL but surely people dont turn there modems off ? but if I wait for a quieter time it will dissapear and I will be able to synch at a higher rate...weird!

[#8]

Hi,

Thanks for all of the attachments - the NE5000 means little to me!

The SNRM plots look much better than that from earlier on ... the QLN means little to me and I found little clarity on how to read them on the internet.  Your plot does though look quite different to those which I did find.

May be @ejs has some insight here?

[#9]

Good morning, QLN is like the noise floor the receiver can see before the ADSL signals are put on the line, so peaks mean interfering signals on those frequencies that will cause reduced snr or even unusable frequencies.

Today we have a classic village REIN plot, blotted out the radio too initially then just bad interference, it's exactly like a large motor starting with a high inertia load (when I was a youngster some factories just had one motor with an overhead pulley and belt system). I sometimes think of grain dryers as the winter barley is starting to come in now. Anyway here you are for amusement!

The filter is to show a good one should have lots of chokes and caps, some of the cheap ones have only one inductor!

[#10]

Please let us know if there's any help from ourselves needed here.

[#11]

Well three things really, is it possible to edit the thread title as perhaps its a we bit unfair and......

What do you think of that peaky QLN plot, could that be VDSL interference ?

And lastly have you seen similar SNR plots from other people living in rural villages ?

Sorry to ask for opinions rather than yes/no, it's just I keep getting splinters from scratching my head to much

[#12]

Moderator's note:

@hitchhiker43

What was you thinking of changing the title to?

[#13]

How about leaving out "Disgusted with Plusnet telephone support"

I might have been at the time but as the thread is remaining here it's not fair for it to be constantly broadcast.

If you can change it, many thanks

[#14]

Moderator's note:

@hitchhiker43

Title changed as requested.

[#15]

Thank you MAV, can you do the other two please ?