Date: Sat, 21 Oct 2000 10:20:13 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: wireless Internet connection from Westy
In-Reply-To: <39F14317.6D80829B@primenet.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 03:17 10/21/2000, t wrote:
>For back to the woods types... carrier pigeons. Only they are extinct.
I've just been cruising in Scamp with a dual-mode (AT&T system) phone. I
used a 3Com Megahertz modem card and $$$ cable to connect with Nokia 6162
phone -- total cost about $450 for the three of them. This is a regular
modem connection, i.e. it shifts to analog mode whether or not there is
digital service available. Cruising the Maine coast, I was getting 9600
bps connections but ended up throttling it to 4800 bps for better
reliability. By leaving the modem audio always on I could hear when it
started getting into trouble. I did not have an external boost amplifier
but it would have been useful (changes transmit power from half-watt to
three watts, no effect on receive). I used an external antenna (another
??$100 including cable to fit the phone antenna jack) hung in the rigging
about ten feet up -- it was a "high feed-point" (no ground plane) 800 MHz
analog antenna and definitely made a difference much of the time. I'd have
put it much higher but had only 15' wire to the phone (swapping loss in the
cable for better line-of-sight). People have used Yagi or other
directional antennae to sight on a tower for better results from a fixed
location.
I was able to use it underway -- however Scamp only moves at 5 knots. I
had to severely throttle the amount of mail I get by receiving it at home
at 15-minute intervals and then deleting all but personal stuff from the
server, also by setting a very small limit on the message size that would
be received without checking (15k I think I used). The system at home had
to be checked regularly because if it gagged I would be quickly overwhelmed
with mail on the boat.
When this was working properly, I could retrieve mail on the boat and only
get personal stuff plus whatever had come in in the last 15 minutes. Large
msgs I would get the first bit and then decide whether to pull the whole
thing. My ISP uses a POP server (as most do), but an IMAP server would be
much better for this sort of work as all your mail is stored on the server
and only retrieved when you specifically ask for a given message or set of
them.
By suppressing graphics I could do extremely limited web stuff. I was able
to upload and download files to the web site I was working on. If I'd had
to move more than a very few images I'd have gone ashore and begged a phone.
david
ps -- in context, I can easily remember when I would have cheerfully
committed regicide for a 2400 bps connection, let alone 4800...does that
make me old?
David Beierl - Providence, RI
http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"
