extending a telephone point

On Mon, 18 Sep 2006 15:37:09 +0100, The Natural Philosopher wrote:

<snip>
Just shows how much you don't know then. You simply haven't worked on an old enough installation. There is a bit of "figure of 8" copper plated steel cored stuff still tacked along our soffit. Now as this place was derelict 30 years ago the original line must be younger than that. Our lines now come in on Dropwire No.10 though.
As to xDSL *requiring* a twisted pair no it doesn't, all it needs is a balance pair and an open line is balanced. Having said that the common mode rejection of an open line compared to twisted pair is going to be worse so the increased noise pickup will limit the speeds achievable by xDSL.
And I few years back I saw some open lines feeding several houses from a pole top. Can't for the life of me remember where. But they were most definitely open line, complete with double porcelain insulators each end etc. They don't install lines that reliable any more...
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 18 Sep 2006 17:51:06 +0100 (BST), "Dave Liquorice"

There's _still_ an extant one not far from here. Most of the drops are in dropwire, but feeding one house is a pair of 40lb wires on porcelain insulators - well, porcelain at the pole end and composition at the sub's end.
--
Frank Erskine
Sunderland
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 18 Sep 2006 21:09:03 +0100, Frank Erskine wrote:

"40lb wires" now that really will confuse the youngsters. B-)
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Dave Liquorice wrote:

Ah...well maybe so. I was involved at the exchanges and with new install only. As far as the channel islands go I was installing Internet for te Tlecos, and the great rivalry between the islands as increased by the fact that whereas Guernsey had faithfully copied BT 'best practice' and installed thick copper twisted pair everywhere, Jersey has used thinner wire to save money, and had extreme issues with longer runs and ADSL..

There are also impedance issues. Its not probably an issue for a shirt run, but you need the characteristc impedance of twisted and a fairly constant 'power factor' over the total line lengthto get ADSL to work.

I don't think they are very reliable. Certainly when I first became aware of telephone lines in the early 80's standard practice was a steel cored twisted pair. I vaguely remember porcelain insulators on telephone lines in the 50';s tho. Our first phone was in the sixties, and IIRC that was installed with twisted pair and steel..not what you describe
I suspect that the porcelain and the figure 8 stuff was discontinued when system X took over. Its probably pre-war..
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nope ! My figure of eight cable was installed post 1984 as it was installed while we have lived here and that's when we moved in. No porcelain insulators though, just a hook plate on the gutter board and a straining tail.
AWEM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Andrew Mawson wrote:

Lord. Where ARE you? Outer Hebrides?
They must have had a few miles on some reels left over.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

discontinued
and
Well if SE London / NW Kent is in the outer Hebrides then yes <G>
AWEM
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 19 Sep 2006 11:05:27 +0100, The Natural Philosopher wrote:

Nope. Late 70's early 80's.
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 22 Sep 2006 22:33:53 +0100 (BST), "Dave Liquorice"

When open wires served insulator "pots" on the corner or whatever of your premises, the feed from there to the "protectors, heat coil and fuse" within the house was more conventional 1pr/12lb tinned copper wire - still figure-of-eight configuration, but much more compliable (is that a real word?!).
In much earlier days, the insulator pots could be very high on a building, in which case special insulators were used with side "knobs" to re-route the open wires down the side of the building to near the entry point.
I've never actually significantly worked on such stuff - almost all my GPO experience was on internal and transmission gear, but we were well informed in those days!
--
Frank Erskine

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Works with ratchet straps, too. When you're securing a load to the roofrack or trailer putting a twist or two in the open sections of strap stops it thrumming annoyingly.
--
Skipweasel
Pay no attention to that man behind the curtain.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 18 Sep 2006 15:10:31 +0100, Frank Erskine wrote:

Dropwire as used for the last 20+ years has been a round cable containing twisted pairs with steel strainers. See my other post, CW1378, Dropwire No.10 (2 pair) or No.11 (3 pair) IIRC.
Old drop wire was as you say a flat "figure of 8" single pair with copper plated steel cores.
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Dave Liquorice wrote:

That is certainly my experience too.

Never seen that.
Not since maybe the late 50's possibly.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The Natural Philosopher wrote:

No, the figure-of-8 stuff (Dropwire No. 6, I think) was in use well into the 80s. When I bought my first house in Cambridge (1979) I had to have a phone line installed and that was what was used.
In the late 50s I suspect you would have got two bare copper wires on moulded (not ceramic, by then) insulators.
ICBW but I associate the coming of the round 2-pair dropwire with the era when people started to have two lines - one for the phones and one for the modem.
--
Andy

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Tue, 19 Sep 2006 13:23:32 +0100 someone who may be Andy Wade

Indeed. I can recall it being installed around that time too.

Indeed. This is how it was explained to me by an employee of British Telecom at the time. They installed the stuff for two main reasons:
1) if there was a fault then there was a possibility that swapping the pairs would clear it rapidly and cheaply.
2) if one had a second line "installed" then they would connect up the second pair, but still charge you for installing a new line.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
remarked:

Most of the cost of which was the exchange equipment, not the drop wire.
--
Roland Perry

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 Sep 2006 21:20:15 +0100 someone who may be Roland Perry

Depending on circumstances that would be true in some/many cases.
--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
David Hansen wrote:

Indeed. The wire coming into the house may or may not be anything from trivial, to many thousands of pounds..
I watched them pulling new cables up the road, and stopped to chat "Run out of pairs mate, some bugger up the road there wants a couple of extra lines, and we are having to upgrade 3 miles of cable so the bastard can get them"
Don't underastaimate what else has to happen on a new line install..wires have to be physically hooked up at the exchange, and the line tested end to end....hopefull VOIP will ultimately mean each exchange is simply an IP LAN wth 10Mbs connectivity for everyone, and off we will all go..Mmm. If video on demand takes off, make that 100mbps..
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 20 Sep 2006 21:20:15 +0100, Roland Perry wrote:

But not the time if you had to fly and fix another completly new cable from the DP at the other end of the street or 4 fields away... Much easier and quicker to connect the spare pair at each end. B-)
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

How about a mains telephone line extender like this:
http://www.maplin.co.uk/Module.aspx?ModuleNo 658&C=Froogle&U658&TB175
I've got the one-for-all version and find it's very good.
Alan.
-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Alan wrote:

Or if you want data rather than voice:
http://www.solwise.co.uk/net-powerline.htm
--
Cheers,

John.

/=================================================================\
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.