Thread: SSB to shore?
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Larry W4CSC
 
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Wayne.B wrote in
:

Is the Kantronics TNC comparable to something like the SCS PTC-IIpro
which is the recommended unit for SailMail?


No, SCS holds the proprietary patent on Pactor II and II used by Sailmail
so you have to give them piles of money if you want to use it.


How would you automate sending a new position packet every hour or so?


You don't do that. Send the APRS packet out every 2-5 minutes or more.
APRS is a "beacon" mode. It broadcasts its data to whatever stations can
hear it. It doesn't "connect" like regular 1on1 packet stations. So, the
more often you send you broadcast packet, the more stations that will hear
it on HF in the fading and noise HF is normally full of.


Is there any acknowledgement that your position report was correctly
received?


No, it's the broadcast mode above. There are no ACKs from stations because
it is not connected to anyone in particular.


Can a position report be sent to APRS via EMAIL?


Not that I'm aware of. Bob Bruninga invented APRS at the Naval Academy
because midshipmen, being the great sailors they are, kept getting lost in
the Academy's boats...(c; So, he designed it to keep broadcasting their
positions at very regular intervals so the Academy would know....A) where
they are....B)they were still afloat enough to have a transmitter and
power. When Bob, WB4APR, an avid ham, gave away his system to the ham
community, that's when it all got out of hand. Maps were drawn of land
masses, lots of new features like automatic weather reporting (the Wx
stations you see on findu.com), emergency beacon messages, public broadcast
messages, hell the hams are even using it with slow scan TV, now.

Bob's website at the NA is:
http://web.usna.navy.mil/~bruninga/aprs.html
Right from the inventor, you can read all about APRS and its capabilities.
It was originally written as an MS-DOS program to run on simple computers,
but has emerged over the years. There are lots of links to Bob's servers
at the Naval Academy's server and other places so you can watch it function
across the planet in realtime. In the summertime, you can even find out
where the Academy's sailboats are with a link on this page. You'll need
java and javascript installed to look at most websites. The websites are
part of the ongoing improvements in APRS coverage.

When the Academy flotilla was in Charleston, Bob called me to ask me to go
down to the boats and see if I could figure out why their master station
quit working. I met the luckiest officer in the Navy. Here he was being
paid to sail some really fine sailboats, full of slave midshipmen, to ports
all over the place. They actually PAY him!.... One wonders whos ass you
have to kiss to get THAT job!