Gubbo
Well-Known Member
Having recently installed a NASA AIS Radar, I was most unimpressed with the minimalist instrution booklet when it came to the attributes of the various settings.
Having sailed last weekend in the Harwich area, it collected lots of information, but I found that the validity was somewhat hit and miss. For example it would track a ship to a point then the display would become "static" even though the vessel was clearly steaming onwards. It was as if the unit had become bored with that particular ship and didn't want to listen to it any longer!
Can you advise what settings you use for the most reliable results. In particular I'm interested in whether you select channel A, B, or alternating A/B?. What threshold level do you have? Which range and update rate gives the most consistant results? How long should I have to wait between updates from ships on the move? Is it just me or do some ships transmit incorrect status messages via AIS (ie moored when steaming or vice versa)?
For info, my antenna is mounted about 10' above the waterline and the ships I was interested in were only between half and three miles away. The ships concerned are North sea ferries and large container vessels so clearly within the AIS class A requirements. I also have proper radar fitted and am aware of the limitations of the AIS unit, but would still like to get the best from it.
many thanks
Gubbo
Having sailed last weekend in the Harwich area, it collected lots of information, but I found that the validity was somewhat hit and miss. For example it would track a ship to a point then the display would become "static" even though the vessel was clearly steaming onwards. It was as if the unit had become bored with that particular ship and didn't want to listen to it any longer!
Can you advise what settings you use for the most reliable results. In particular I'm interested in whether you select channel A, B, or alternating A/B?. What threshold level do you have? Which range and update rate gives the most consistant results? How long should I have to wait between updates from ships on the move? Is it just me or do some ships transmit incorrect status messages via AIS (ie moored when steaming or vice versa)?
For info, my antenna is mounted about 10' above the waterline and the ships I was interested in were only between half and three miles away. The ships concerned are North sea ferries and large container vessels so clearly within the AIS class A requirements. I also have proper radar fitted and am aware of the limitations of the AIS unit, but would still like to get the best from it.
many thanks
Gubbo
