clear@cavebbs.gen.nz (05/21/91)
In article <telecom11.372.7@eecs.nwu.edu> Fernando da Silva writes: > I'm trying to connect an American RJ11 male connector to a British > CW1311 socket, for data communications purposes. Connect 3 and 4 on the RJ11 (red and green) to 2 and 5 on the BT. The easiest way to do this is get a standard four-wire cable and twist the outer two pairs at one end. A straight-through cable simply will not work. We've had to make adapter cables like these for years, ever since foreign modems were allowed to be sold here. Some modems are sensitive to line polarity. The RJ11 3&4 is referred to as "tip" and "ring", the BT 2&5 is called a "line pair". If you get don't get dialtone from the above, try swapping 2 and 5 over in the wall socket (its easier than fiddling with tightly crimped connectors). Administrative note: every RJ11 I have ever seen has been made from clear (but brittle) plastic. You can tell at a glance what wires go where. Every BT plug I've ever seen is moulded in white. You have to hold them up to a 100W bulb and peer very closely to tell how it is wired ... 8-) Charlie "The Bear" Lear | clear@cavebbs.gen.nz | Kawasaki Z750GT DoD#0221 The Cave MegaBBS +64 4 642269 V22b | PO Box 2009, Wellington, New Zealand
Julian Macassey <julian%bongo.UUCP@nosc.mil> (05/21/91)
In article <telecom11.372.7@eecs.nwu.edu> fds@cs.man.ac.uk (Fernando da Silva (PW Ph.D.)) writes: > I'm trying to connect an American RJ11 male connector to a British > CW1311 socket, for data communications purposes. > RJ11 jack CW1311 jack > 1- not used 1- not used > 2- black(?) 2- red > 3- red(?) 3- blue > 4- green(?) 4- green > 5- yellow(?) 5- white > 6- not used 6- not used > For most British phone connections only 2 and 5 of CW1311 are > sufficient. Wich are the two important lines on the RJ11? Are all > four lines important for data communications? On the RJ-11 jack, the two center pins (3 - red & 4 - green above) carry the phone line. The ringing signal is also supplied on the "red and green". In the UK, there is a ringing signal on pins 2 and 5 though most UK phones derive ring signal from pin 5 and s signal from pin two connected to pin 3 via a 2uF capacitor. UK extension phones use the capacitor in the jack. US phones have the capacitor in the phone. Julian Macassey, n6are julian@bongo.info.com ucla-an!denwa!bongo!julian 742 1/2 North Hayworth Avenue Hollywood CA 90046-7142 voice (213) 653-4495