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Path: utzoo!linus!genrad!decvax!cca!ima!johnl
From: johnl@ima.UUCP
Newsgroups: net.micro
Subject: Re: Racal-Vadic VA3451 triple modem - (nf)
Message-ID: <343@ima.UUCP>
Date: Thu, 16-Jun-83 18:38:47 EDT
Article-I.D.: ima.343
Posted: Thu Jun 16 18:38:47 1983
Date-Received: Fri, 17-Jun-83 09:00:37 EDT
Lines: 30

#R:sri-arpa:-211200:ima:16900010:000:1430
ima!johnl    Jun 16 14:17:00 1983

Funny you should ask about the Vadic 3451PA modem and MCI.  That modem
has pulse dial only, which is no good with MCI.

Just last night I crocked up a dialer routine that uses the Vadic and a
Ven-tel autodial modem (which does do tone dialing) hooked to the same
phone line to make uucp calls via MCI.  It wakes up both modems, then
hands the Vadic the local MCI number followed by many "pause" digits.  It
waits a while, then tells the Ven-tel to dial the rest of the digits to
be handed to MCI, but as soon as the Ven-tel has dialed the digits,
aborts the Ven-tel's call and goes back to listening to the Vadic which
was pausing in the meantime, which then figures that it's done dialing
and listens for an answer tone.  Even under the best of circumstances, it
only works about half of the time.  It seems that with two "phones" on
the line, MCI doesn't reliably hear the digits that the Ven-tel dials.
Yetch.

My advice is to get a triple modem only if it's absolutely necessary,
i.e. the system you want to call has Vadic-only modems and won't get any
212 modems.  There are lots of 103/212 modems that work a lot better, and
are much cheaper, such as the Hayes Smartmodem 1200 which you can get for
about $500 - $600.

John Levine, IECC, PO Box 349, Cambridge MA 02238; (617) 491-5451
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