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From: julian%bongo.UUCP@nosc.mil (Julian Macassey)
Newsgroups: comp.dcom.telecom
Subject: Re: Payphones and DTMF Dialling
Message-ID: <15761@accuvax.nwu.edu>
Date: 3 Jan 91 05:51:01 GMT
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Reply-To: Julian Macassey <julian@bongo.info.com>
Organization: The Hole in the Wall  Hollywood California U.S.A.
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X-Telecom-Digest: Volume 11, Issue 4, Message 8 of 12


In article <15648@accuvax.nwu.edu> hpa@casbah.acns.nwu.edu (Peter
Anvin) writes:
X-Telecom-Digest: Volume 10, Issue 902, Message 3 of 10

>jack.  (By the way: all the four RJ11 wires are mandatory in Sweden
>and are supported by the phone network: there are TWO
>twisted-pairlines (for a total of four wires) in the local loop to
>each line.  Maybe that has something to do with it.

	This must be something new. When I was in Sweden (1970s),
there were only two wires needed. Phones given to me by Ericsson and
Televerket in the 80s also only need Tip and Ring. The telephone ICs
made by RIFA (Ericsson) are also two wire devices.

	So what is the second pair of wires used for?

	Any Ericsson or Tele people care to comment?

	Silly trivia: Swedish phones have the world's lowest minimum
current spec - 12 mA. The U.S. is 20 mA although a 2500 set will
usually work fine at 14 mA.


Julian Macassey, n6are  julian@bongo.info.com  ucla-an!denwa!bongo!julian
N6ARE@N6YN (Packet Radio) n6are.ampr.org [44.16.0.81] voice (213) 653-4495