How about a Vesper Marine
WatchMate 850, WatchMate Vision or XB-8000 AIS transponder instead?
All of these will trigger an alarm when the MOB1 is activated.
In the case of the WatchMate 850 and Vision it will show the MOB directly on its integrated screen
and give you an alarm and trackback.
In the case of the XB-8000 it will trigger a dedicated alarm/buzzer/etc directly attached to the unit and also show it on mobile phones and tablets.
Sorry for the product plug
, but thought you might want to know if you don't already.