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This month we're giving away the Zeroplus Logic Cube logic analyzer that I review later in this issue. This is a top-of-the line model that goes for $2149.



By Jack Ganssle


Published 4/22/2004

"Amber 2, this is Rescue 103", the VHF squawked at me in July of 1992. I'd left England 31 days before, alone, bound across the North Atlantic in what turned out to be a mostly bad weather trip (more at But after an 8 day gale my mast had failed, fuel was low, and I was still 500 miles from the US. I had set of an emergency locating device that broadcast a coded message to orbiting satellites, which in turned relayed my distress call to a ground station.

The Halifax-based four engine Canadian P-3 hove into view just four hours after I activated the transmitter. Their response to my virtual mayday completed an electronic web of connectivity. My beacon had squirted off a one-way, unacknowledged, short data packet echoed Earthward by a spacecraft. The message contained a unique serial number encoded in the bit stream. The rescuers not only got my distress message; they knew who I was.

That's a far cry and a huge advance in technology from 1978 when I tried to signal an aircraft from a 6 foot liferaft while adrift in the Caribbean. That beacon had no smarts; it was not much more than an oscillator broadcasting a warble tone on aviation's 121.5 MHz distress frequency. The signal went unheard; passing fishermen eventually saw my decidedly low-tech flares.

In 1999 a buddy and I sailed my current boat from Baltimore to Antigua, a 17 day passage interrupted by one unexpected stop in Bermuda to top off on diesel and rum. Voyager carried an Orbcomm email transponder, a very sophisticated box that exchanged data with low-Earth-orbit satellites when they passed overhead. A built-in GPS automatically sent our position via the spacecraft to a web site a few times a day. Friends and family checked our progress on the web page's chart; they freaked when the signal disappeared for a couple of days. Bad weather destroyed the antenna, which we eventually replaced with a coathanger. I suspect we're still the only boat to communicate with a spacecraft over a rusty old bit of crooked metal.

For a while I communicated via ham radio while at sea, but that's only legal for non-commercial purposes. So each port found me racing to town, searching for Internet cafes. It wasn't unusual to find a windowless building with a dirt floor, chickens wandering amongst the modem and USB cables. I was astonished to find that the entire country of St. Vincent's and the Grenadines had but a single 28.8kbaud link to the rest of the world a few years ago.

The pursuit of a better email solution led to a satphone for last summer's voyage to San Salvador and the islands downwind. It was a wonderful, and a horrible, solution. 9600 baud meant excruciatingly long transfer times. The satellite was in view for only about 10 minutes each hour. I'd perch in the companionway, book in hand, looking at the signal strength meter every minute or so, till the signal peaked. Then a quick dash below to the laptop to start exchanging mail. But just having any email service at all was a godsend.

Today we expect `net access everywhere, pretty much all of the time. It's part of the fabric of life, like electricity and telephone service. Yet even those expectations are new. Sailors a century ago were out of touch for months to years. I once asked my late grandmother if she had a phone while growing up in New York City around 1910. "We knew someone across town with one of those," she replied. My kids were aghast. They, of course, IM and text message constantly. The slightest routing problem brings an immediate chorus of "Dad, the net's down!"

In the 60s we were content with one week UPS service. Fedex changed our expectations to overnight a decade later. That was too slow; the 80s saw universal adoption of faxes. Today email is even faster.

What's next? The embedded community underlies all of these technologies, so it's we who will invent the next bit of even more instantaneous communication. How many more ways can we interact? IM, television, voicemail, text messaging, email, web, cameras in cell phones. sometimes I just want to say "enough already!"

The satphone gave us email, but it was eerie to be anchored in front of some stunning deserted island, tranquilly kicked back, rum in hand. and hear the phone ring.