Category: AIS

Wasn’t I just noodling about celestial mechanics? Well it turns out that for the first time since 1998, the time authorities need to insert a second into the world clock “to make up for...

So goes the headline in the Nov. issue of Digital Ship (click on link in “Navigation” section, and thanks, Raye), but there’s something odd about this otherwise very intriguing proposition. For one thing, SRT’s business development...

Go to this page to see a series of screen grabs illustrating a scary close call between the 32’ ketch Valhalla and the 132 meter tanker Miri Cahaya. I’d almost guess that the tanker...

The above snip from a Nobeltec VNS screen (full size here) shows how some of the megayachts tied stern-to at the Ft. Lauderdale show looked AIS-wise. There are obviously a few errors either in the vessel dimensions or...

What’s wrong with this AIS target, seen off Naples, Florida, a couple of weeks ago (with the Si-Tex receiver)? How about a bogus MMSI # (only 4 digits), no name, and destination as “HOME”...

Today, I’m afraid, we must speak of “frequency agility.” Part of the Class A standard is that transponders must be able to change channels if ordered to by the presiding local coastal authority. The digital command is received...

Finally I have some specifics about the Class B AIS transponder standard, which is “very close” to finalization: • Like Class A, static data will be broadcast every 6 minutes on alternating channels. A...

It turns out that Nobeltec has decided to market the Si-Tex (Nasa) single frequency black box “AIS100” receiver instead of the Comar SLR-100 as I had first presumed. I dare say that this move, along with adding AIS...

I felt like a spy in an old WWII movie, rigging a VHF antenna and GPS on the patio outside my hotel room late at night, then hunching over my laptop hoping for certain transmissions…but,...