We had a thunderstorm on Sunday night. Spectacular lightening all
around us. I saw it approaching and disconnected the TV and computer
etc. Fully expected a power cut, but it didn't. But on reconnecting
the computer after the storm had passed, no broadband connection, no
dialing tone, no nothing. Quite dead. Even the test socket in the
linebox was dead. However, ringing neighbours on our mobile showed we
were the only ones without a land line connection. Engineer duly
arrived yesterday; linebox had blown. Replaced it, and all now OK.
But what is it in the linebox that blows? A quick internet search
talks about spark gaps and the like, but I haven't found anything that
suggests a fuse. So what blows, and why is it so integral to the box
that the whole box has to be replaced?
On Thu, 14 Apr 2016 10:02:11 +0100, Chris Hogg wrote:
There's a 'lightning arrester' (they probably call it something else)
across the line. I suppose it could be a MOV but I've no idea really.
I would guess that could go short circuit. As for replacing it, that
would involve soldering, and more effort 'cost' than a new box.
Seems likely. If it did, it would short the line and render it inop (it
would give 'busy/engaged' if called from another line.)
(='.'=) Windows 10: less of an OS, more of a drive-by mugging.
On Thu, 14 Apr 2016 10:29:35 +0100, Mike Tomlinson
That makes sense. I tried dialing our land line number with our
mobile, and got a recorded message that the line was engaged. So the
surge suppressor was blown; presumably not a direct hit on the
telephone line (overhead, hereabouts), as I would have expected our
neighbours to be knocked out as well, but enough of an EMP to blow the
On Thu, 14 Apr 2016 20:04:02 +0100, Dave Liquorice wrote:
Is exactly right! :-)
On a BT exchange, you'd expect to receive an unavailable announcement or
NUT when calling a number that has a loop fault (unless called within 60
seconds of the fault developing or after the S&Z cycle period if the
fault occurred whilst on an outgoing call and the called number hung up
on the call).
Getting PET for hours/days/weeks of such an "off hook" fault is
typically the case with Talktalk exchange equipment (and possibly also
the case with all of BT's competitor telco exchange equipment).
On Thu, 14 Apr 2016 16:13:18 +0100, The Natural Philosopher
Years ago I used to maintain a Philips office phone system in rural
Wales. It got zapped frequently, and each time the whole unit had to
So when it happened again we took a closer look, and one of the BT
lines feeding it ran very close to a long run of wire fencing.
After re-routing this dropwire, it never again caused trouble.
Well BT Openreach replaced our NTE5 front plate today - telephone no dial
tone or incoming calls, Internet connection working fine. Presumably the LF
part of the filter - can't be much to them so quite surprised it was that
that had popped it's clogs
On Fri, 15 Apr 2016 13:29:26 +0100, Andrew Mawson wrote:
Lack of a DC path kills the phone but ADSL/VDSL uses radio frequency
carriers and can get across small gap. This knocks the speed back but
the 'net still be there.
They are actually quite a complex of capacitors and inductors, I'd
still go with a fried track breaking the DC loop. Especially if the
'net was still there at full whack.
Is the faceplate one with a filtre in it? Sort of surprised BT
replaced that, they only have a requirement to deliver POTS to the
test socket behind it. Ok the facplate is part of the NTE but it only
needs to provide POTS.
Yes Internet was still going as strong as ever (21 Mb/s). NTE5 faceplate has
the filter in it and is BT supplied so surely they'd have to fix it as it
is their property ? Sadly no fibre - our fibre equipped cabinet is over a
mile away :(
On Fri, 15 Apr 2016 22:33:30 +0100, Andrew Mawson wrote:
Not "Superfast Broadband" then. Has to be over 24 Mbps to qualify for
that title. 4 to 5 Mbps ADSL2 here and no chance of ADSL2+ or VDSL,
not that either of those would make much difference to the speed at
the end of 3.5 km of line.
I guess so, things move on. Is the default now a filtered face plate?
Fibre has a range of 10 km + and thats with 32 way PON split. Take
out the split and several to many 10's of km is possible. Have you
asked BT for a fibre connection? You find that there is a fibre node
nearer to you and install costs may only be a grand.
Or are you using the term "fibre" to mean VDSL? Which at a mile is
going to have degraded to more or less the ADSL2+ speed that you,
presumably, currently have.
It's a rural situation here albeit only 50 miles from London. Recently BT
Openreach have installed two VDSL cabinets in the village on minor roads,
adjacent to the original voice cabinets. So it's fibre from the tiny village
exchange to the new VDSL cabinet, then copper mainly underground but some
overhead the 1.2 miles from the house to the cabinet.
As the farm gate is on one of the only two trunk roads in East Sussex, and
our nearest neighbour is half a mile away, I see no prospect in the sensibly
near future of fibre getting much closer - they won't dig up a trunk road to
equip one house !
On Sat, 16 Apr 2016 08:43:47 +0100, Andrew Mawson wrote:
This is what normally happens though they did plant a number of new
copper line cabinets around here as the cable joints were in
The fibre cable may not pass through that exchange at all and even if
it does it'll only be a patch panel to ease utilisation of the
currently dark fibres in those cables. The fibres from the VDSL
cabinets around here go to Hexham 40 odd km away before they hit any
active routers/switces WHY.
That's the PITA, BT use 1 km line length from the cabinet as a rough
guide for the provision of "Superfast Broadband". Our line was an
"exchnage only line" no cabinet, so no VDSL. However they installed a
cabinet outside the exchange, trouble is that is 3.5 km away. There
are occasional mutterings of G.Fast but from what I've read about
that it just bumps up the speed available over the first few hundred
(tens?) meters of copper, does SFA for those more than a 1 km or so
from the cabinet.
You may find that fibre is already running along those roads, in fact
I'd almost put money on it. All the exchanges have been fibre linked
for a very long time, though some remote tiny "garden shed" exchanges
might be on a radio link. Have a look for rectangular manhole covers
every 200m or so, either in the road surfce or verge. Ones in the
verge might be hard to find as they are so rarely opened they become
completely over grown. Probably have "Post Office Telephones", "GPO"
or "BT" markings. Then you need to find the nearest "fibre node",
this is point where the fibre cables are jointed to extend on or to
split. This gives access to the fibre cable and the possibilty of
"Fibre to the Premisis On Demand" with the exccess construction only
charged from the node, not the nearest exchange with (customer) fibre
There is a brand spanking new fibre cable running 10' from our front
door, to feed the VDSL cabinet in the village. The team installing
the duct for it said that there was to be a fibre node in the next
chamber upstream, ie 200m away. So FttPOD might be possible or FttRN
(Fibre to the Remote Node). That is a small robust VDSL box, designed
to live up a pole or in a hole serving a small number of customers. I
believe they don't need a mains electricity supply, being powered
from the connected customers over the copper pair but not sure if BT
are using that.
They will if you pay... It's about £100/m to dig up a road. B-)
On Sun, 17 Apr 2016 02:00:10 +0100 (BST), Dave Liquorice wrote:
Forgot to mention Openreach have a scheme called "Community Fibre
Partnership". If a group can be formed, in a suitable area, to come
up with some fraction of the install cost Openreach will install
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