I went down the boat to do some maintenance
this morning, and thought I'd see what was out and about today. As it's mid march many boats are still to be launched (parking is a challenge as the boatyard is full of boats!).
I now have a file created from my boat. This is the AIS output from a Standard Horizon GX2100 connected to a an aerial mounted about 12m above the waterline (normal position on top of the mast) fed into my onboard laptop
. I.e it is a single antenna
and I've not left my mooring
inside Portsmouth harbour. The aerial is nothing special and I have hills and land between me and some of the targets.
and before anyone starts harping on about Sunsail, Britania or any other commercial
organisation, there are 12 sunsail yachts in this, but I can predict where they are going to so they are not a problem (they broadcast their routes before they race, so anyone listening can work out what they are up to if they are worried) and the main racing season has not started - the private racers are more of a problem as they often get given their courses before taking to the water
(so no way for anyone to predict where they are going) and some seem to think the colregs including a right of way for racing craft - the cry of "don't you know
I'm racing" has been heard many times.
The 2 files have 135 and 139 targets shown in them. The larger file has data collected over about an hour, the other is a shorter time period. As there is a limit to some attachment sizes, I've added them by adding pdf to the extension (is there a better way to do this ?) just loose that and unzip them and Opencpn
should play them.
my onboard display is a 19inch, 1400x900 monitor
- so I shouldn't be short of real estate to display it on
This is early in the season and will get much worse over the next month or so, but already I think you can see the problem we face. I'm out sailing tomorrow, so will create another file whilst I'm underway and post that as well.
and as an added comment, I met with someone from the Southampton
VTS a few days ago, and whilst they log all AIS transmissions and keep them incase of an incident for a month, they disable display of Class B transmitters on their working screens as they generate too much clutter! If that is the case for people who stare at the screens to navigate large vessels, then those of us who glance at the chartplotter
only every few minutes have a bigger problem.
Anyway I hope this is helpful, I'll post the other log tomorrow
Regards and good sailing