[CA] [CA11] AIS Lost Connection (C90W C12OW C140W)

[Stoomy]

Thanks Chuck,
Sorry for not including a full list of electronics...I didn't want to bore anyone.
My system is currently configured with a C140W at the helm acting as master, connected to a C90W inside at the nav station. The two MFDs are connected to Raymarine Digital Radar and each other via SeaTalk HS (ethernet switch). The C140W is connected to the N2K backbone via SeaTalk NG --> N2k adapter. The Only source of GPS data is the C140W's internal gps. The C90W has internal GPS disabled and is usually powered off. The symptoms I'm describing occur both with the C90W on and off.

I recently completed a passage from Boston to Bermuda and back. The "AIS Lost connection" alarm does not seem to occur in Boston Harbor (Where there are plethura of targets...so I think your explanation here fits my situation:

If this problem could be mitigated by sending the MFD "heartbeat communications (proprietary)" referenced by the Raymarine Moderator in this thread: http://raymarine.ning.com/forum/topics/c...onnection, I would like information on what that signal is to see if I can duplicate it.

Thanks!