julian@bongo.uucp (Julian Macassey) (10/10/90)
In article <13005@accuvax.nwu.edu>, TOBY@brownvm.brown.edu (Toby Loftus) writes: > I have a friend who is going to the UK soon and has a modem which will > support CCIT (?) protocols, which I understand are used in the UK. > What I would like is any information on how to physically connect the > modem to the UK outlets. I'm told that the UK has modular plugs, but > ones quite different from US plugs. Any suggestions on how to attack > this? Any company out there which supplies cords with a UK plug on > one end and a US plug on the other? I suppose this should become one of this groups "Frequently Asked Questions". Below is a file I keep on this matter. I hope it helps. Yes, I know various countries have silly protective regulations about what you can do with the service you are paying too much for. But I am interested in telecommunications not restrictive practices. British Telecom Auxiliary Jack Wiring British phones have 3 wires. There are two wires A & B (Tip & Ring) coming into a house. There is no protector. In the primary jack in the house is a 2 uF capacitor. On the end of this cap is the third wire. The AC ringing signal is fed to the phone on this wire and its DC counterpart. See diagram: ----| |------O (3) | | (A) O----------------------O (2) (B) O----------------------O (5) Note: The Numbers in the diagram are the numbers engraved on the jack terminals. If the phone rings continuously, reverse 2 and 5. The ringer is fed by AC current on pins 3 and 5. BT consider the A terminal to be ground. B is measured as 45 to 50 volts above ground. Wiring Colour Codes: The standard inside wire is classic "3 pair". A jack is wired as follows: Pin # Wire colour 2 Blue/White 3 Orange/White 4 White/Orange 5 White/Blue END So if you have a US device that you need to wire into a UK jack this is what you do. Get a US line cord and cut the jack off one end. Go to your local UK electrical shop and have them terminate the end with a UK jack. The center two wires in a US line cord are the phone line, so they should terminate on UK jack pins 2 and 5. Then you plug the UK end into the wall and the US end into your phone, modem, answering machine etc. You can also buy a line cord with a US plug on one end and spade lugs on the other. Using a screwdriver you screw the line cord onto the terminals in a jack or junction box. This works all over the world. Julian Macassey, n6are julian@bongo.info.com ucla-an!denwa!bongo!julian N6ARE@K6IYK (Packet Radio) n6are.ampr.org [44.16.0.81] voice (213) 653-4495