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HAMming
It Up
by
Mark Sedenquist
In
the last couple of weeks the Road Wirer has received some
questions about using the HAM radio network instead of cellular
to access the Internet on the road. Megan and I have met a
number of HAMs on the road who are using HAM radios and it
might be a good alternative for some of our fellow Dashboarding
pioneers. Amateur radio operators use the AMPRnet or Amateur
Packet Radio Network. The AMPRnet supports the Internet protocols
of TCP/IP, TELENET, FTP AND SMTP. It also supports the Packet
Radio protocols of AX-25, NET/ROM and PBBS.
There
are a number of abbreviations that users of e-mail and local
area networks, (LAN) use every day without knowing what they
are. One of the things I try and do is to demystify some of
these odd terms and so a quick time-out: TCP = Transmission
Control Protocol and IP = Internet Protocols were developed
by the U.S. Government under the aegis of DARPA = Defense
Advanced Research Projects Agency thirty years ago. In the
last fifteen years the TCP/IP has come to be signify all of
the combined protocols that have been developed to enable
e-mail and web retrieval systems to operate. But the one I
like the best is PING. When I first heard these term, way
back in '96, my web guru-of-the-time sent a "ping"
down the Internet path to test the routing path for a brand
new Web site known as RoadTrip America. I assumed it was some
sort of magical electrical signal. It actually was a "Packet
Internet Gopher" that traced the routing path through
the gateways to determine which of the local stations were
active. Now, you know more than you probably wanted about
"Pings!"
Back
to amateur radios: There are a number of bandwidth allocations
used by commercial and amateur radio users. Within the amateur
bandwidths there are established frequencies which are reserved
for packet data radio use. In each geographical area, local
HAM groups have constructed repeaters which pick up the weak
signals of mobile radios and then retransmit them at a higher
wattage. In order to operate an amateur radio, a person must
be licensed by the FCC. The easiest license to obtain, that
allows access to the radio packet network, is the "Technician
Plus." Information about how to obtain this license can
be found at The American Radio Relay League, www.arrl.org
Once
licensed, an operator needs a transceiver, a PC, the appropriate
software to gain access to the packet radio network and an
antennae. One of my Road Wirer correspondents, Patt
Kipp estimates that such a set up can be obtained, (except
for the PC) for about $1,000. There are some difficulties,
first this is an amateur system and any use in a business
application is prohibited by US law. Second, the routing system
is less efficient than the public telephony used by the generalized
Internet and substantial delays in delivery of e-mail can
occur. Third, an operator needs a permanent base station,
even if one's normal transceiver is mounted in a vehicle.
For the needs of the Road Wirer this is not a perfect solution,
but one that you might want to consider.
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