What's happened?

My house move completed yesterday with the line being connected and fibre also. Initially Plusnet had 'accidentally' provisioned me on the unlimited package despite me being on the unlimited extra in my previous house. When first connected yesterday, these were my stats:

Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 18.5 20.0
Attenuation (dB) 19.5 0.0
Output Power (dBm) 12.4 4.0
Attainable Rate (Kbps) 84485 16190
Rate (Kbps) 39998 1999

Now, after 2 disconnects (not of my doing!!) overnight, they are:

Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 6.1 6.3
Attenuation (dB) 19.6 0.0
Output Power (dBm) 12.6 7.6
Attainable Rate (Kbps) 57039 16078
Rate (Kbps) 57031 16112

Obviously I'm not super impressed with my download speed. My attenuation looks all wrong seeing as I'm only about 147m from the cab.

My previous house, despite being only 5 door away was about 500m from the cab due to line being routed differently via an SCP but I managed to get a constant 65Mbps there with an attenuation of 18!

No point contacting Plusnet yet as they'll tell me they can't do anything until after the mythical '10 day training period' but anyone got any ideas why my attenuation is so high and snr so low?

So the figures previously were an anomalous on the Downstream ...

Those now all tie together reasonably nicely.

Can you be sure you are only 147 metres away ... the attenuation is more consistent with a 600m line length. Where did the 147 come from?

An Openreach engineer I was talking to next to the cab last week. Also, my neighbours either side and across the road all get rates in the late 60s to early 70s. There is still noise on the line in the background, could this be causing it?

Edited by WelshWArrior (Thu 18-Jun-15 08:26:52)

How did he come up with the figure?


Given the attenuation has remained the same with the resets, I would guess it is accurate.

I think he was working on the house directly opposite as I saw an Openreach van parked outside about 20mins later.

Could the noisy line cause low snr and high attenuation?

Just did a check on the availability for neighbours either side of me with their phone numbers, I got this:

High Low High Low
FTTC Range A (Clean) 80 80 20 20 -- Available
FTTC Range B (Impacted) 80 61.9 20 12.2 -- Available

Which is more in line with the stats I saw when first connected yesterday.

Edited by WelshWArrior (Thu 18-Jun-15 08:50:55)

Did he actually do any measurements on your line?

Noise could cause low SNR however does not affect attenuation. Attenuation is mainly due to the line length and gauge of wire with very minor effects caused by the actual termination impedance of the modem and a some other factors.

Hmm something strange is going on. I just spoke to next door neighbour and he confirmed he gets a constant 74meg and he's further away from the cab than me. Also, the checker results I posted above for the neighbour the other side suggest that I should be getting a hell of a lot more download speed don't they?

Engineer didn't do check on my line - I just asked him how long it was.

Edited by WelshWArrior (Thu 18-Jun-15 09:22:14)

Looks like something is wrong based on the BTw check results...

Plusnet will look at getting the voice fault fixed first before anything else...

In reply to a post by WelshWArrior:

Engineer didn't do check on my line - I just asked him how long it was.

So, he just plucked a number out of the air. Do you really think he knows the length of every line?

Of course he doesn't and to be honest, I don't care what he said the line length is. What I DO care about is that the houses either side of me are getting late 60s early 70s down (which is supported by the checker results I posted for my next door neighbour) which means so should I.

I can literally throw a stone and hit the cab. There are BT manholes outside each house coming up from the cab and I know the cable comes straight up the hill past my house.

I just measured on Google Earth and I know it's only rough but got 163m from the cab to where the drop cable comes into my house.