SRT, blowing the AIS doors off

... written for Panbo by Ben Ellison and posted on Aug 17, 2009

In 2005, when Software Radio Technology talked about a Class B AIS transponder retailing for $500, I expressed some skepticism.  But "good work takes time" (as I often say about my home-built home), Class B has almost reached that price point in 2009 (largely thanks to SRT), and -- holy cow, Batman -- wait til you hear what they've got in the pipeline.  For starters, how about a small, high performance Class A transponder that will cost "well below $2,000" and will be available to client companies (SRT sells nothing direct) "at the end of 2009"?  And apparently that's as both an OEM product virtually ready to ship or as a two-board module ready to get additional features (like NMEA 2000 output) and/or be integrated into ECDIS, plotters, VHF radios, etc...

And that's not all.  How about a full dual channel AIS receiver with the "exceptional sensitivity...normally associated with Class A transponders" and an expected retail below $200, not to mention a go-anywhere sibling module that's only two-inches square?

SRT_2nd gen AIS receiver PCB.JPGOr how about the smaller, and fully waterproof, Class B transponder below?  SRT doesn't mention its possible price point, nor a release date for the B or the receiver products, but the press release suggests that all these developments share some common technologies. Which leads me to wonder if Class B won't nicely beat the $500 number by late 2010, about five years after it was ambitiously advanced. (Which is way better than my house.)

SRT_2nd gen Class B AIS.JPG
So should you be bummed if you already bought an AIS receiver or transponder?  Nah; the good news here is that eventually there will be lots more AIS-equipped vessels of all sizes.  And, by the way, I did have an inkling of these developments before I wrote last week's AIS rumination.  But I didn't know about the press release SRT issued to the trade, and which is now in the public domain.  I can't find it online, but thanks to a Panbo friend, you can download the PDF here.  Enjoy!



Are you suggesting that recreational vessels might bne able to afford and therefore use AIS class A? Was that foreseen by the designers of the standard? The AIS communications protocol gives Class A priority over class B and has a finite maximum capacity (I think around 2000 vessels in any one area).

Posted by: at August 17, 2009 6:49 PM | Reply

Here's a unit with all the features you were describing:

For sale in the US here:

I have no affiliation with those companies, just noticed the press release in Lattitude 48.

Posted by: Patrick at August 17, 2009 9:07 PM | Reply

Marius, there are plenty of yachts voluntarily carrying Class A AIS now, and there will be more when the price and installation hassle is reduced. Any vessel is allowed to carry either class of AIS, and the authorities do not seem concerned about overcrowding.

Patrick, Comar's AIS Multi looks like an excellent receiver, but I believe there will be ones as good or better at half the cost, not to mention receivers built into other gear.

Posted by: Ben at August 17, 2009 9:50 PM | Reply

Have you noticed how Simon R. Tucker has found a line of business (Software Radio Technology) that has the same initials as himself (SRT)... Cool!

Posted by: Kees at August 18, 2009 2:54 AM | Reply


You are right about receivers being built into other devices. Vesper Marine is introducing their AIS WatchMate RX which combines all the great features of the original AIS WatchMate with a very sensitive, dual channel receiver, all in one housing. It will be available at the end of September with a MSRP of $699. Maybe we can get you one to try on Gizmo? In the interest of fairness I do have to disclose that I am the US distributor for the Vesper Marine line of products.

Posted by: Steven at September 1, 2009 12:17 AM | Reply

ComNav Marine now has the SRT Class "B" AIS on the shelf and retailing for $899 in the US.These are available through any ComNav dealer.Check their dealer list on their website at

Posted by: Dave at December 11, 2009 3:45 PM | Reply

Thanks, Dave. I see they also have the compact Class A, though it's not yet FCC approved and thus it's not actually priced or for sale yet. But, wow, it has NMEA 2000 output!

Posted by: Ben at December 11, 2009 5:33 PM | Reply

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