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[snadge]

Hi

I have installed my new Zyxell VMG8924-B10A (latest fw) and have it up & running with DSL-stats, looking at the Bit-Loading and QLN it appears that something is eating into the SNR which looks to be around 5-10Mbps worth of bandwidth that is lost.

I know its going to probably be impossible to fix, but you never know lol...

here are some screenshots from DSL-stats, between tone 40(ish) and 400(ish) is the suspect. The telephone cable runs from the front doorway through the hall, up & down door frames a few times, then into the living room which has a well-used filter and the usual crappy DSL (flat) cable which is about 6 foot long into the VMG8924, the telephone cable is round so I'm guessing it is CW1308 TP

the spikes are:
TONE 140 (603.7kHz) - BBC Radio 4 in North East
TONE 161 (694.3KhZ)
TONE 248 (1069.5kHz)
TONE 267 (1151.4kHz)
TONE 282 (1216.1kHz)
TONE 338 (1457.6kHz)










thanks

[GigabitEthernet]

Get a filtered faceplate and a better quality DSL cable.

[niemand]

Not sure how a filtered faceplate is going to help with this, the ingress is within the range the plate admits? Might help a bit I guess if the filter set up is more open to outside interference.

Is your phone line on poles or underground, snadge? If it's on poles that's almost certainly where the majority of the ingress is getting onto the line.

[snadge]

Not sure how a filtered faceplate is going to help with this, the ingress is within the range the plate admits? Might help a bit I guess if the filter set up is more open to outside interference.

Is your phone line on poles or underground, snadge? If it's on poles that's almost certainly where the majority of the ingress is getting onto the line.

@ CarlT - Yes, it is a drop wire fed from a pole & JB..  I was looking at the new Mk 4 VDSL Faceplate over at Run-IT-Direct which he sells with the new NTE5C Faceplate for £24... this setup has an RF3 filter in... do these RF3 filters affect the VDSL signal at all?

edit: it is a line out to the pole (25ft?) and then underground from there

[j0hn]

The NTE5C + MK4 are of a much poorer construction than the NTE5A + MK3.

There's nothing new in the MK4 filter that will help with FTTC.

[snadge]

The NTE5C + MK4 are of a much poorer construction than the NTE5A + MK3.

There's nothing new in the MK4 filter that will help with FTTC.

whats bad about the Mk4 compared to Mk3...?

i will have to go to ebay as RITD only sells Mk4 or the crap XTE thing

[j0hn]

None of the internal components on the MK4 are soldered into place like they are on every other version of the MK filters.
Push and click components, assembled as cheaply as possible.

The general consensus is the older generation are better constructed.

I've swapped a couple NTE5C+MK4's for NTE5A+MK3's for friends/family and find the latter also perform better.

Run-it-direct charge a fortune anyway, particularly the delivery charges. Don't limit your options to their stock levels.

edit: to add, the MK3 also has an RF3 filter, that's not unique to the MK4.

[snadge]

ok i will scour ebay for a Mk3 & some Cat5E/6 with RJ11/45 connectors on

[j0hn]

How long a length will your patch cable be?

In my case my line is over 1000m from the cabinet, with a 0.5m patch cable.
Having 1000m of CW1308 then half a metre of Cat5e seemed a bit pointless.

If your patch cable is a short length (under a meter or 2) then Cat5e will make little to no difference.

Of course if they are the same price then it wouldn't hurt to use Cat5e, but don't rule out CW1308 if that's all that's available.
I haven't checked eBay in a while but all the rj11/rj45 patch cables used to be CW1308.

For a longer run between modem/router Cat5e makes sense.
Cat6 can be extremely awkward as a patch cable as it's very inflexible.

[burakkucat]

I have installed my new Zyxell VMG8924-B10A (latest fw) and have it up & running with DSL-stats, looking at the Bit-Loading and QLN it appears that something is eating into the SNR which looks to be around 5-10Mbps worth of bandwidth that is lost.

I wonder . . . Are you referring to the DSPBO notch that is present in your Bit loading per sub-carrier and QLN per sub-carrier plots by any chance? If yes, then there is nothing that you can do about it. It is a feature related to the CAL which, in turn, is related to the distance between the telephony serving exchange and the PCP.

[ejs]

None of the internal components on the MK4 are soldered into place like they are on every other version of the MK filters.
Push and click components, assembled as cheaply as possible.

The components of the MK4 SSFP itself look soldered.
https://www.youtube.com/watch?v=jD67a-ZC7VY
The NTE5C is push and click.

[j0hn]

The components of the MK4 SSFP itself look soldered.
https://www.youtube.com/watch?v=jD67a-ZC7VY
The NTE5C is push and click.

The fact the MK4 is soldered doesn't reassure me much though.
It still only fits on the NTE5C.

I did assume both were similar construction though so thanks for the correction.

[snadge]

@BK - i was on about the bit on the first download band where the noise spikes are eating right into my SNR

see here:


some good news though, my router has re-synced at a much higher speed, dont think the new router is the cause as I was informed that DLM (after an amount of time) would sync me higher if errors were low, INP was 3 and Interleaving was 1370, now INP=0 and Interleaving = 1, meaning my sync has gone up from 73MB to 79MB ...happy days  however in doing so the MAX DATA RATE has dropped from 87MB to 79MB

            Downstream   Upstream
Line attenuation (dB):     14.2      0.0
Signal attenuation (dB):   Not available on VDSL2      
Connection speed (kbps):   79032      20000
SNR margin (dB):           6.3      9.6
Power (dBm):               3.4      3.3
Interleave depth:          1      1
INP:                       0      0
G.INP:                     Not enabled      Not enabled

the patch cable is one of those 1.5M things, the replacement will be 3M in length

[j0hn]

That will likely be the new modem that caused this.

The line has been active for more than long enough for it to have changed to fastpath with the previous ISP modem.

The combination of the BCM63168 and the extra common mode noise filter on the Zyxel can greatly reduce errors, triggering the DLM.

You will likely see a big jump in ES now the line is fastpath.

On the errors tab on DslStats it gives an hourly average of ES.
You need to remain under 120/hour or 2880 per 24 hours to keep fastpath.

Excellent result 

[snadge]

@ j0hn - ahh i see, what is this "extra common mode filter"..? does my previous router a BTHH5B which is also Broadcom 63168 not have it too?

Iam getting about 80 ES P/H