Missing AIS targets

[tonyburn]

I have recently installed EasyAIS linked to a Garmin chartplotter which is working fine most of the time. However, recently when sailing in the solent I have noticed that a number of commercial vessels are not showing up even though clearly visible, one example was a ferry which when behind me was clearly visible on screen, when it came passed it disappeared from the screen. Has anyone else come across this got an explanation

 

[tom52]

Missing targets had their AIS switched off ?

 

[deep denial]

Yes that happens to me sometimes. I have the feeling that the problem reduced when I changed from using the vhf aerial with a splitter to using a dedicated AIS aerial on the pushpit. What sort have you got?

 

[MOTORBÅD]

Do a Garmin software update. Early Garmin plotters would only show 5 to 10 AIS targets on the screen.
Did an update on 5012 plotter from version 2.7 to version 5.20, and the all targets now show.

Michael