Connector for cut telephone cable?

Not possible to just replace the cable?

If not, twist and solder each conductor and insulate with heat shrink sleeving. Then one sleeve over the lot. Will be as neat as any connector.

You should not solder a telephone connection while it is still connected to the exchange. The soldering iron will be earthed and will short out the voltage supplied by the telephone exchange.

Glue lined heatshrink for the outer, not plain heatshrink.

If this cable is multi-stranded, then the other connector options would be using screw terminals. I'd be disinclined to use those outdoors. If you do, you're hacking, so just use any alarm wiring junction box and put that in turn inside the best weatherproof housing you can find.

If this cable is solid core (standard phone wiring) then prefer IDCs or even better, jelly filled crimps, rather than screws. Jelly crimps (be nice to a phone installer) in a reasonably weatherproof box would last well.

"Weatherproof" is best achieved by sticking the cables up through the bottom of the box, pouring potting compound over that to seal them in and then only using the lid's gasket seal to seal the box. Don't rely on gaskets or glands to seal around phone cable, especially not if it's non-round. If you had too, wrap self-amalg tape around to make the cable diameter up to fit the gland. Compression glands don't seal well on narrow cables.

Also arrange premises wiring so that the ADSL filter (I assume you have intaweb access) is done in the master socket's faceplate (Solwise will sell these, if you don't already have one) rather than a plug-in microfilter and then have the "suspicious" internal wiring for extensions done on the premises side of the filter so that it's only carrying phone signals, not the ADSL too.

I'm guessing it won't work for you, but if you can site the join inside one option would be to fit an additional extension socket. Having extra phone sockets is always handy. If that doesn't provide enough length to fit in the middle of a tight cable run, fit two sockets (don't have to be adjacent) and run a new piece of cable between them.

Theo

Not all soldering irons have earthed tips, many have a high resistance instead to eliminate static.

Having said that, if the OP is uncertain, I would recommend unplugging the iron whilst in contact with the wires, relying upon residual heat which should be sufficient.

Which the telephone exchange is designed to cope with for long periods.

As the OP mentions it's feeding a telephone _extension_, hopefully the supply end of it can be isolated first before any soldering work.

Thanks all. Yes as it's the extension I can isolate it. The iron I have is Weller kit which has (I think - will check) a floating 24 V xformer in the basestation part.

That won't be a problem. In my 17 years as a cable jointer on BT I've had to chase many an earth fault that, if we were busy, the subscriber may have reported days beforehand. If the exchange can withstand a genuine earth fault for days at a time, a few minutes with a soldering iron won't bother it.

Mind you, talk of soldering and epoxy is a bit OTT to be honest. If the joint has to be outside, exposed to weather, ask the next Openreach guy you see for an external joint box like this

On Mon, 27 Jul 2009 15:48:34 +0100, "Pete Zahut" had this to say:

A few minutes? A second or so, more like... :-)

Or use a gas one...!

Pete Zahut wibbled:

Just to add:

Cheers

Tim

Can't say I've seen those in use anywhere. These though are everywhere from fronts of houses to tops of poles:

It's an assumption on my part, from when I used a soldering iron to rejoin my phone cable and there were sparks whenever the soldering iron touched the wires. This was in the days before computerised exchanges. I imagine the phone company has rules about not connecting voltage from a malfunctioning device to their lines. Otherwise I have 400,000 volts available, and I could possible find a Telharmonium! :)

There is about 50V DC on a line and about another 220V AC when its ringing. The 50V is shorted when you pick up a phone and its the short that indicates you are making/answering a call. Shorting it to earth will draw no more current so you can't harm anything.

Having a cr@p soldering iron that isn't earthed (or having a ceramic insulated shaft) is far more dangerous as that could put 250V AC on the line and give an engineer a belt. It won't do much to the exchange as there are voltage limiters to reduce lightning induced surges.

But you are right there are laws against putting voltages on the telephone lines and they would probably persecute you.

Try 50V / 75V when ringing

Or 90V if it was Telex. Yes, you could feel the difference.

The ringing generators are 230V.

I was higher on ISDN too.

From a hi-z source it drops very rapidly if you actually try and pull any current. It's still enough to give you an "ouch" if you are soaking wet standing in a puddle. BTDTGTTS, putting on the control and music lines for an outside broadcast (Swap Shop IIRC) I forgot that there was a DEL on the block as well kept getting this belt...

Bollocks ringing on a POTs line at the NTE is between 40 and 100v RMS, 25Hz (+1Hz - 4Hz).

No dear, that's the one with the big square brass pins. Now sit quiet and drink your cocoa.