September 2006 Archives

Garmin AIS revisited, a dite dissappointing

Today I thought I’d see how well the latest 3210 software (version. 2.6) handles input from the SeaCas SafePassage 300 (it’s got a model number now because Fred has added two new versions). The results were better than last time; for instance, the megayacht Floridian, (visiting again), revealed its name and other important info (bigger image here), and the AIS control menu sub tab is available, letting users specify what zoom levels show AIS and whether target prediction lines are based on time or distance (and how much). But I was a little surprised by what’s missing, and asked Garmin for confirmation/explanation:

1) The 3210 does not yet calculate CPAs…”We wanted to see how reliable and accurate the AIS system really was before giving users automated monitoring. We felt it best to not give users a false sense of security if in reality AIS data transmitted by most ships was inaccurate.”

2) It also won’t list targets, a feature that I think I’ve seen on every ECS and MFD that handles AIS. But Garmin’s comment, “Can you help us understand what such a list would be used for?” is interesting. Nothing came to mind instantly (besides hunting for megayachts); I usually do query AIS targets graphically, putting the cursor over one and hitting “enter” for more info (as above, the only way possible on the Garmin).

I guess the good news here is that Garmin is supporting AIS at all. I dare predict that CPA calculations will come eventually, maybe even a target list, especially if you all make a case for why in the comments section below.

Meanwhile, you may wonder what’s up with the rusty coffee can in the background left? That’s part of my testing gear, a GPS signal inhibitor! I was hoping that if I forced the attached Garmin GPS 17 to lose position, the unit might pick up the position being sent by the SafePassage (as is done by the Raymarine E-120, sort of; it gives priority to the NMEA 0183 SafePassge, but will pick up a NMEA 2000 GPS if the SafePassage loses signal). No such luck, even when I totally uninstalled the GPS 17.

Shanghai dawn, with pretty darn good radar

Crack of dawn, really, and nearly flat calm as we’re inside Cape Cod Bay, Race Point/Provincetown on the port quarter. In the bigger version of this picture you can see some shore lights around the entrance to the CCC, as the Canal is called, from whence that ship emerged. You can also see the remnants of the bothersome light leakage I wrote about the other day, coming off the steaming light just below the compass and a little also off the green running light forward. Note that the engine gauge lights aren’t on because my mate Rich is actually running the boat from below, and Volvo automatically switches gauge lights with engine control (nice).
   But I had been up on this bridge from the very wee hours of the morning and, though it was clear, had much appreciated the quality of the Raymarine radar. Check the screen shot below, full size here; with the E-120 set head up at 24 mile range, that’s Race Point off my port bow, a MARPA target in the ship channel to Boston, and Cape Ann on the starboard beam. I’ve used the VRM to note that the boat’s relatively dinky 4kW dome scanner is seeing the Boston RACON buoy about 32 miles away, which seems quite good. A couple of days later we ran into thick fog when entering Fisher’s Island Sound and learned that this radar could also distinguish little outboard boats at close range, again all settings on ‘auto’. Impressive. I think the scanner may be one of Raymarine’s new models, which they’ve been rather quiet about, but I need to check that out. Eventually I will also tell you about the problems we had with this radar (nothing to do with the scanner).
   In the meantime, have a wonderful weekend, which is a three or four day end-of-summer Labor Day special here in the states. If you’re anywhere near me, you really should check out Windjammer Weekend, especially today’s gathering of the fleet.