Path: utzoo!attcan!uunet!mcsun!ukc!tadtec!tjfs From: tjfs@tadtec.uucp (Tim Steele) Newsgroups: comp.dcom.modems Subject: Re: Do US-made modems work in the UK? Message-ID: Date: 25 Oct 90 14:53:14 GMT References: <1990Oct16.133001.271@computing-maths.cardiff.ac.uk> <1990Oct22.235230.1401@cbnewsi.att.com> Sender: tjfs@tadtec.uucp (Tim Steele) Organization: Tadpole Technology plc Lines: 43 In-Reply-To: hrs1@cbnewsi.att.com's message of 22 Oct 90 23:52:30 GMT In article <1990Oct22.235230.1401@cbnewsi.att.com> hrs1@cbnewsi.att.com (herman.r.silbiger) writes: > In article <1990Oct16.133001.271@computing-maths.cardiff.ac.uk>, gae@computing-maths.cardiff.ac.uk (Geraint A Edwards) writes: > > If I buy a modem in the US, will it work fully on the > > phone system in the UK? > > > > Is it legal? Are the tone-diallings compatible/fully-tolerant? > > Are even the plugs the same? > > > > Has anyone any expreriences in this area (anonymity respected) > > and are willing to enlighten me? > > > > US modems will work fine in the UK, just be sure that it supports the CCITT > protocols as well as the Bell protocols. Must current modems do. > > Tone dialing is the same allo over the world. > > The wall line jack requires a different plug, but thr telset jack is usually > a RJ-11. However, instead of pins 2&3 being tip and ring, in the UK it is pins > 1&4! Not quite right, I'm afraid. I posted a detailed explanation some time ago; here's a summary. 1) The line plug is different. In the UK, the plug is 6 pin, although pins 1 & 6 often aren't wired. The line is on pins 2 & 5; pin 3 is used for earth recall (PABX) and pin 4 for anti tinkle (to suppress phone tinkling when pulse dialling). 2) The ringing / busy tones are different, which confuses self-righteous modems (hello Hayes!) which tends to interpret UK ringing tone as busy, for example. 3) It is *a criminal offence* to connect a non-approved device to the UK telephone network. Offenders are liable to a *prison sentence*. Tim -- tjfs@tadtec.uucp ...!uunet!mcvax!ukc!tadtec!tjfs Tadpole Technology plc, Science Park, Milton Road, CAMBRIDGE, CB4 4WQ Phone: +44-223-423030 Fax: +44-223-420772 Telex: 817316 TADTEC G