Posts like these caused me to review our AIS/MFD documentation... and so far, I'm pretty sure I have no way to filter out by transmission class. This with a Furuno FA-70 Class B+ AIS, and a TZT3 MFD.
I can show/not show all targets. I can show/not show identification info (a name), but a target symbol appears either way. I can highlight (and audibly alarm) targets based on CPA/TCPA. I can hide targets moving slower than X speed. Zooming the screen in and out changes how many AIS targets are visible at any given time.
Nothing offers any choices based on Class B, B+, or A. (That I've found so far... and I can generally read the manual well enough...)
I can show/not show AIS targets on the Garmin screen, next door... which is my radar display. I think I can bag the AIS names if I wanted to. I can do the CPA alarm. I can bag the alarm for slow targets. No way to surpress a subset by transmitter type.
Maybe that's a thing Class A systems can do? Or urban myth?
-Chris