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From: Cliff Yamamoto <cyamamot%aludra.usc.edu@usc.edu>
Newsgroups: comp.dcom.telecom
Subject: Re: A Couple Tech Questions About Cellular Phones
Message-ID: <10608@accuvax.nwu.edu>
Date: 8 Aug 90 20:21:03 GMT
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X-Telecom-Digest: Volume 10, Issue 551, Message 12 of 13


In article <10573@accuvax.nwu.edu> gnu@toad.com (John Gilmore) writes:

>rpw3%rigden.wpd@sgi.com (Rob Warnock) wrote:

>> I have no idea whether there is any magic a cellular CO can do to
>> create an "infinity tap" without causing ringing.

>The US cellular telephone standard defines a way to "ping" a cellular
>phone without making it ring.  I don't think the
>standard specifies an audio path to the microphone/speaker during this
>operation, but individual models might 'extend' the standard that way.

As the originator of this thread, I guess the answer boils down to
"it depends on the model".

>[I used to have a copy of the cellular standard document, "EIA IS-3",
>but it's been a few years since I dug it out.  I got it for $32 plus
>from Global Engineering Documents at +1 800 624 3974.  It may have
>been revised since then ('87); they will check if you ask them.  I
>recommend that anyone with a technical interest in cellular get it;
>it's the real live protocol that runs over the radio.]

My thanks to John for passing on this info.  In my original posting, I
also wondered if there were some sort of defacto standard (i.e. EIA,
ANSI, IEEE).  Many have mentioned the Motorola book from William C. Y.
Lee, but not anything official.  Anyway, I just called and ordered my
copy from the above source.

   Doc #        cost    hndlng   UPS    CA tax   total
EIA/TIA-553    $52.75 + $5.00 + $5.00 + $3.93 = $66.68
Revised 9/89

Seems recent enough for me.  BTW, Global Engineering Documents is
located in Irvine, California so I'm sure anybody out east can call
till 4 P.M. PST/PDT.

Thanks to all who responded to my post.

Regards,

Cliff Yamamoto