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From: mikey@trsvax
Newsgroups: net.micro
Subject: Re: Networking portables via radio and.
Message-ID: <53400067@trsvax>
Date: Fri, 13-Sep-85 10:20:00 EDT
Article-I.D.: trsvax.53400067
Posted: Fri Sep 13 10:20:00 1985
Date-Received: Tue, 17-Sep-85 05:40:46 EDT
References: <1018@brl-tgr.ARPA>
Lines: 25
Nf-ID: #R:brl-tgr.ARPA:-101800:trsvax:53400067:000:1088
Nf-From: trsvax!mikey    Sep 13 09:20:00 1985




Cellular phones won't work for modems.  At least not now, and not with
off the shelf modems.  

I know some people who use Radio Shack model 100's and 200's on their 
phones, and they get OK results, but the problem is cell handoffs
droping the carrier.  Also, 300 baud is EXPENSIVE over a cellular phone.

Even when you are sitting still, the cells can be reconfiguring, causing
problems with modems.  Sure, you can get manual modems that won't
hangup on a dropped carrier, or even modems that are modified so that
the timeout is lengthened for drop, but then you're talking "custom",
not off the shelf.  If it is for a dedicated use, I'd use 1200 bps
modems wired directly to the phone.  Since the phone is half duplex
except for the handset, you can wire direct from the Rx and Tx portions
of the modem and not use it's filters.  Both modems (at the host and 
at the portable) will have to be modified to not drop line on short
carrier interuptions.

There are probably a host of other problems, just that these are where
I'd start before I'd lay out my game plan.

mikey at trsvax