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[sheddyian]

A friend with ADSL is on a long line, resulting in fairly slow synch speeds (circa 6,000 - not bad I suppose).

Their internal phone wiring is minimal, there's only the one master socket, into which a filter and the phone and the router are plugged in.

I'm guessing the answer to my question is "no, you idiot!" but I was idly wondering - is there anything to be gained (performance/speed wise) from fitting a VDSL filtered face plate there?  Given my assumption that there's more in them than in the usual plug-in filters, and (perhaps?) they're of a general higher quality overall.

Thanks

Ian

[Weaver]

How much of an improvement you get depends on the quality of the microfilter you've got already of course. But anyway the BT faceplates are very high quality so you should go for it,

The ADSLNation faceplate filter is a very good device too, recommended if the phone is causing problems de-stabilising things.

[burakkucat]

I would add to Weaver's reply by suggesting that an experiment with, say a Mk 3 SSFP, would be the only way to obtain a definitive answer.

[sheddyian]

Thanks, I may give it a go.  I was tempted to do so anyway, but then I saw the prices seem to have gone up on ebay somewhat since I last bought one - I had it in my mind they were in the region of £5?  I saw £18 for a complete lineboax + vdsl set, or around the £9 mark for the vdsl plate alone.  Maybe I misremember. 

Anyway, having seen the cost of buying one on a whim, I thought I'd ask the question here to see if the tinkering was worth it.

[of course, tinkering is always worth it!]

I took a snap of the router stats summary, any thoughts on these :

Code: [Select]

ADSL mode G.DMT

               UP    DOWN
Line Speed     896   6624
Attenuation    25.0  37.5
S/N Margin      7.0   6.0


The Kitz max speed calculator with that attenuation suggests 7328 for dslMAX or 10656 for adsl2+ 



Ian

[burakkucat]

Here are two eBay suppliers offering SSFP Mk 3s at a far more reasonable price (£4-50) --

http://www.ebay.co.uk/itm/GENUINE-BT-Openreach-MK3-VDSL-faceplate-/172120365457
http://www.ebay.co.uk/itm/GENUINE-BT-Openreach-MK3-VDSL-faceplate-/191832928875

My immediate thought is to suggest using ADSL2 (G.992.3) mode rather than G.Dmt (G.992.1) or ADSL2+ (G.992.5) modes . . . assuming that the modem/router can be so configured.

[G.992.3 is the mode of choice both in Weaver's croft and The Cattery.    ]

[sheddyian]

Here are two eBay suppliers offering SSFP Mk 3s at a far more reasonable price (£4-50) --

http://www.ebay.co.uk/itm/GENUINE-BT-Openreach-MK3-VDSL-faceplate-/172120365457
http://www.ebay.co.uk/itm/GENUINE-BT-Openreach-MK3-VDSL-faceplate-/191832928875

although there's then postage of £3.90 or £3.25.. I didn't remember the total being that high in the past.  Had a vague memory of buying complete linebox + vdsl plate for around £10 including delivery in the past.  I'm being picky, I should just order one.

My immediate thought is to suggest using ADSL2 (G.992.3) mode rather than G.Dmt (G.992.1) or ADSL2+ (G.992.5) modes . . . assuming that the modem/router can be so configured.

[G.992.3 is the mode of choice both in Weaver's croft and The Cattery.    ]

The router is a fairly recent cheapy TalkTalk one with only 2 LAN ports on the back, but I'm unclear on the model number.  I'm assuming it's set up out-of-the box so would imagine it's trying different modes before settling on G.Dmt as best choice for the line?

I'll certainly try forcing it into ADSL2+ mode though, and see what happens.

Ian

[sheddyian]

Just to add...

Earlier, for a few minutes, I had the brilliant idea of leaving a Raspberry Pi there, running routerstats that I could then monitor remotely to see how the line behaves, look at tones etc.

Then realised there's no way the TalkTalk router is going to have telnet enabled, is there? 

Ian

[sheddyian]

The ADSLNation faceplate filter is a very good device too, recommended if the phone is causing problems de-stabilising things.

This was the first faceplate I had; later changed to a BT MK3 when I was trying to limit the effects of once or twice weekly 1-2 hour bursts of REIN from what I assumed to be a faulty spare-room TV nearby.  (It eventually went away on it's own, presumably the TV died).

The ADSLNation faceplate worked well for me, in eliminating ADSL noise from voice.  Even with two plug-in filters in series, there was some ADSL noise still present on the phone, the ADSLNation plate resolved this.

Later, I discovered there was an unbridged tap that was probably contributing to the audible noise on voice.

One quirk I did notice, and Burakkucat may remember, is that I found I got better signal to noise margin or attenuation rates (I forget which) with certain RJ44 leads over others, and it was repeatably consistent.  There was a particular lead that always performed better, even though, spec wise, it wasn't especially good.

I later found out this was an affinity caused by the ADSLNation plate; once I'd changed to the BT MK3, I could see very little difference in reported performance between different RJ44 leads.

Ian

[burakkucat]

I'll certainly try forcing it into ADSL2+ mode though, and see what happens.

No.    Not ADSL2+ (G.992.5) but ADSL2 (G.992.3)!

However if it is the usual TalkTalk supplied bottom-of-the-reject-pile device, it may only have two configurable modes -- off or sort-of on! 

[burakkucat]

I somehow sense that your quest for telnet access to the TalkTalk supplied device will be in vain.

On the subject of leads, yes I can remember you finding one that consistently performed better than any of the others. If I am remembering correctly, it was a give-away lead that cost less than 2p to manufacture. (As the time is now silly o'clock in the morning, I'll take your mention of "RJ44" to be RJ11 (or RJ12).)

[sheddyian]

I somehow sense that your quest for telnet access to the TalkTalk supplied device will be in vain.

On the subject of leads, yes I can remember you finding one that consistently performed better than any of the others. If I am remembering correctly, it was a give-away lead that cost less than 2p to manufacture. (As the time is now silly o'clock in the morning, I'll take your mention of "RJ44" to be RJ11 (or RJ12).)

Yes!  As I typed RJ44, I knew it sounded wrong, but couldn't remember what it was.  RJ11 is what it was.  And, whilst the magic lead in question was a thicker-than-average RJ11 lead, it wasn't anything special, but performed better than other fancy screened or twisted or any other RJ11 leads I tried.

This difference disappeared when I moved to the BT Mk3 plate, no discernable difference between RJ11 leads.

Ian

[NewtronStar]

This difference disappeared when I moved to the BT Mk3 plate, no discernable difference between RJ11 leads.

Ian

The Mk3 SSFP has a balun choke installed it's set to unbalance and only receive the frequencies it was designed for but it's not 100% it's more like 60-75%

[ejs]

Personally, I found that the grand total of:

- replacing an old LJU master socket with an NTE5a
- getting rid of the star wiring arrangement, which included a bit of not twisted-pair cable, although this bit has been re-connected to the front plate of the NTE5a using the spare green pair in the existing cable
- fitting an Openreach MK2 SSFP (which was the one more readily available at the time I bought it)
- using a CAT5e modem lead

made virtually no difference whatsoever to the performance and behaviour of my line.

[sheddyian]

This difference disappeared when I moved to the BT Mk3 plate, no discernable difference between RJ11 leads.

Ian

The Mk3 SSFP has a balun choke installed it's set to unbalance and only receive the frequencies it was designed for but it's not 100% it's more like 60-75%

Ah! I see! I think 

So the balun choke is there to negate wiring discrepancies / imbalances?  This might be helpful on a long line?

Ian

[sheddyian]

- replacing an old LJU master socket with an NTE5a
- getting rid of the star wiring arrangement, which included a bit of not twisted-pair cable, although this bit has been re-connected to the front plate of the NTE5a using the spare green pair in the existing cable
- fitting an Openreach MK2 SSFP (which was the one more readily available at the time I bought it)
- using a CAT5e modem lead
made virtually no difference whatsoever to the performance and behaviour of my line.

I've tidied up a few wiring setups, especially where the internal wiring was poor/messy, and always seen an improvement in speeds and/or reduction in attenuation, admittedly to varying amounts.

If this particular slow-line also had lots of internal sockets, I would definately have put in an MK3 plate straight away, but as there's no other sockets I was less clear if it'd help.

It's now on order, so hopefully will arrive just after Easter and I'll report back if I see any improvements.

Ian