That gives you a sync speed of just under 12Mbps, for which you should see download speeds of 10-11Mbps.

Line speeds can deteriorate over time, as the increased take-up causes noise which affects your line. For that reason, the checker gives a range that should make allowance for that.

However, the sync speed is under the bottom of the Impacted range (which allows for poor house wiring), and a long way under the clean range (which is for clean internal line installations).

With those numbers, BT would probably get an engineer out.

Or would you rather do some troubleshooting first yourself?

The attenuation of 33dB is a big clue to the line length, irrespective of the impact of home wiring they line is pretty long, 22dB is around 1.3 km if feeble brain is recalling numbers correctly at the end of the week so something that is 1.8km long might be possible.

This fits in with user description of just over a mile, i.e. the BT estimate is wrong basically. This may be because they are a long way from the DP as I believe the estimates are often to the DP and if you have a long drive etc this is not taken into account.

Edited by MrSaffron (Fri 13-Mar-15 18:27:18)

For info, DP is approx 350m from the property in a rural location.
Most of the cabling from property to the DP was recently replaced.
ADSL service gave approx 2.3Mbs down.
As MrSaffron notes it does look like an optimistic VDSL estimate given the distances.

So the follow up questions are
- what is the best combination of ISP/router/modem for VDSL over long lines (1.5 to 2 km) which gives a reliable service, and
- at which point is it better to stick with ADSL?

Usually the HG612 or ECI modems do the job quietly and well

As for sticking with ADSL, depends on what speeds you get with ADSL, plenty of people getting 2 to 3 Mbps will happily upgrade to 10 Mbps from VDSL2, i.e. its an individual decision to be made on things like is an extra xyz Mbps of upload speed worth the extra money?

I investigated dropping to Infinity 1 but this would cost more(!) as I'm on a discounted deal on Infinity 2.

BTOR was out and checked the line back to the cabinet but found no issues. They advise they have done all they can. Speed is approx 10Mbs down, 1Mbs up, but this occasionally dives like today to < 0.1 Mbs down, whilst up stays at approx 1Mbs. Restarting the OR Huawei HG612 modem brings it back to 10/1.

Is there anything further I can do to keep the service stable?
Manually switching the modem off and on is a pain.

I recall in the earlier days of ADSL the Netgear (model DG834G I think) was more tenacious than other routers over long line copper broadband. Any similar wisdom or experience with long line VDSL2 modems/routers or tweaks to the setup would be welcome.

G.Inp is currently being rolled out and should help. I can't see how restarting the modem would restore speed. I think restarting the router would though.

Is the modem a model 3B, with a white power plug, or is it the earlier one with a black power plug? Whichever it is, does it get quite hot, rather than just a bit warm?

A 3B has it on the label underneath.

Edited by RobertoS (Mon 23-Mar-15 23:03:22)

It's a 3B with a white plug. It does get warm, but not very hot.

Should be OK then, but it might be worth trying a new one off eBay. Including swapping the plug.

Thanks RobertoS.
HG612 unlocked now in place. Performs like original modem, with 11Mbs download speed dropping to 2Mbs or less on occasions.
At least I can gather the stats now and restart the modem using the webgui to increase line speed again.
I've started to read up on VDSL - mainly from info provided by the experts on this forum - thanks guys.
Would still be interested to hear if further tweaks to improve long line perfomance or other recommendations.