SNR up/downupdownup/ like a yo-yo - bad line?

{take a deeeeeep breath}

After trying now for two/three months to get my line sorted, I am still having real issues with it, and ANOTHER engineer is to visit me Monday.

Bit of history: About 5 ~ 7 years ago, some digger cut through the main phone cable up the street from me, killing all the phones (and ADSL) in the area. It took BT about 4 days to fix it. My line wasn't very good after that (I lost about 1mbs d/s). But it all worked fine and stable.

Now to the present, the first engineer swapped out the wire pairs, tested and said all was good. It isn't, same old rubbish connection - disconnects etc started about 12 hours of him leaving. But one thing he said when he was here was he saw a glitch about about 120 metres away, which to him indicated the green box.

Well, since then I wondered, and the green box isn't 120 metres away from me - it is more like 40. So I fired up Google earth and tracing the path from my property to the green box, then using (a guessimate) of the sewer lines in the roads I traced to where the original cable was cut.

Guess what I got? First attempt, 123 metres! Try again, using variance as I am guessing the route of the sewers - 117 metres. One final try, 121 metres! Coincidence? I think not - possible bad repair now showing up.

To me, now, it looks like the fault is between the green box and the exchange, not from my property to the green box.

An example - when I got up this morning, router stats 59160 SR EC's, 11040 CRC errors and 54320 Header errors. I had to reload ATM interface to get connectivity.

Now, after I rang my ISP this morning to get Engineer out, my router resynced twice since then (about 2 hours apart). I have very few errors now (BTW, I am on 4mbs cap as line is so poor):

DS Channel1	  DS Channel0	US Channel1	  US Channel0
Speed (kbps):	          0	        4544	         0	         886
Cells:		          0	       80553	         0	    10638705
Reed-Solomon EC:          0	          41	         0	           0
CRC Errors:	          0	           0	         0	           0
Header Errors:	          0	           0	         0	           0
Total BER:		  0E-0		 0E-0
Leakage Average BER:	  0E-0		 0E-0
Interleave Delay:         0	           7	         0	           0

Would BT do something remote when they get the ticket in?

BUT, I have be monitoring SNR, and it is all over the show:

http://linicks.net/stuff/snrUPdownUPdown.png

Is this normal? Does this show a bad line?

I just dunno what to do now.

Nick

Edited by deleted (Fri 15-Mar-13 17:46:40)

still no interleaving ?

Been there, done that. Yes it is on, if I set router to itu.dmt it shows, and before the 2 resync today it showed, but now nothing as I have no errors at all.

Which makes me wonder that something got changed to stop the errors (also I had stupid BER error rates, like 7568E-12). Current stats since 14:00 today:

DS Channel1	  DS Channel0	US Channel1	  US Channel0
Speed (kbps):	          0	        4544	         0	         886
Cells:		          0	     1506865	         0	    38767155
Reed-Solomon EC:          0	         115	         0	           0
CRC Errors:	          0	           0	         0	           0
Header Errors:	          0	           0	         0	           0
Total BER:		  0E-0		 0E-0
Leakage Average BER:	  0E-0		 0E-0
Interleave Delay:         0	           7	         0	           0

Can the line between the green box and the excahnge be changed 'on the fly', i.e. like some sort of switching?

Something happened.

I dunno.

Nick

Well, today (and I was monitoring), I got a disconnect at 10:10 and now sync at 3072 (AGAIN) and capped at 2.71mb.

THEN I got an unexpected call from a BT engineer. He wasn't a broadband guy though, just a phone guy and he said he had a ticket to check my voice line ONLY.

Of course, everything is perfect and passed. I showed him my graphs of SNR all over the shop, and the disconnect etc., but he said he wasn't a BB guy so didn't know. Told me to call ISP to get a BB engineer out - I said I had etc,

I called ISP when he left, and I still have BT engineer around Monday.

So I dunno what is going on. I think BT are trying to prove my line is OK when it certainly isn't.

Nick