Telephone Line Advice

[binthere]

Most telephone lines to new properties are 2 wire systems 49v wired to terminals 2 and 5 to a master socket, why if we take take a pair off to an extension and use a normal Solwise socket (not master)connected to 2 and 5 does it interfere with other phones connected to the master socket,but does not interfere if another master socket is used with a plug in broadband filter.

[Guest]

Most telephone lines to new properties are 2 wire systems 49v wired to terminals 2 and 5 to a master socket, why if we take take a pair off to an extension and use a normal Solwise socket (not master)connected to 2 and 5 does it interfere with other phones connected to the master socket,but does not interfere if another master socket is used with a plug in broadband filter.

Quick guess is you have not cut out the resistor in the slave socket

[WatchdogSecurity]

shouldnt the line in connect to AB, then the extensions are wired out through 2 and 5, if you parallel wiring of the incoming pair, im sure you will need another master, as 2 and 5 are after the master circuitry, correct me if im wrong.

[camerabloke]

im pretty sure you are right watchdog

[Guest]

now im learning... what resistor OH?

Oops, i meant capacitor, if you use master sockets everywhere they will pull down the voltage and stop the ring tone at other locations.

[Guest]

2 and 5 yes. but you need 3 to get tone.

[Monteey]

Most telephone lines to new properties are 2 wire systems

Correction ALL phone lines to ALL properties are 2 wire

but you need 3 to get tone.

Not if you are using broadband filters, or most modern telephones

[avcctv]

I always used A and B in the master and then subsequent secondarys came from 2, 5 and 3. I always took 3 as being the ring generator. If using a master as a secondary I would snip out the capacitor.

[Guest]

You do not need 3 at all to make it ring

I have fitted over 100 extension sockets, just by using 2 and 5.

Normally Blue/white and blue/white (bt colours)

They have all rung without any 3 connection

This article explains how to wire a UK telephone extension. You are allowed to install extension wiring so long as the connection to the master socket is via a plug, or in the case of the master socket with a detachable lower half, via the connectors on that section. If you decide to connect directly to the master socket or install/replace a master socket you should be aware that you are in breach of your licence to use the phone service and your service provider may charge if they have to come to rectify a fault caused by your efforts (it is rare for them so to do unless you have been really ham fisted). NEVER connect un-approved devices which take power from the mains to the telephone system. Even if you survive the mains on the cabling the poor wireman sitting in a muddy hole some way away trying to find a fault may not.

Master Socket

This is what a typical master socket looks like. You must have one of these at the point at which BT wiring ends and yours begins. Master sockets should not normally be used for extensions.

Extension (Slave) Socket.

All extension sockets are like this. Note absence of ringing capacitor and surge arrrester. The connectors shown are Insulation displacement types (IDC), Extension sockets (especially if bought in DIY sheds) often have screw terminals.

Fixed Upper section

This is the BT supplied NTE5 master socket found in many installations, this particular one is made by Austin Taylor (http://www.austin-taylor.co.uk/). Internally it is functionally similar to the master socket above but the components are protected by a plastic cover.

User removable lower section

When the front screws are removed the complete lower portion of the socket including the IDC connectors for user wiring can be pulled out. They connect to the back plate by means of a fixed plug. The fixed plug is a standard BT plug and socket and allows all the internal wiring to be easily isolated for fault finding. A normal phone can be plugged directly into the socket remaining in the wall to test if the line is OK.

[arfur mo]

hi all,

'3' is 'bell supress', this was really for pulse dial phones as without it, as you dialed it it would cause a 'jangle' on other handsets. most '2 wire' handsets today don't need it or care about polarity, but some do. so to comply and so keep regulation standards (and i'm very big on that stuff as you all know) you should link the 3 from the master to all the '3's on the slaves.

it used to be called A B & BC (for bell capacitor). if your into pain, get an old pulse dial phone, have fingers in touch with line and dial out, great as a 'lads party' fun, measuring how far each 'contestant' is thrown across the room.

Chubbs old 999 dialer units had exposed large screw down terminals on the pcb's, i learnt real quick to keep my fingers well away from them on test calls. great fun though attatching a legnth of flex, open end's bared and then stuff up leg of unsuspecting trainee's shorts while unit dialing out, i can still hear the screams of many victims.

regs

alan