Powering the SP160 Splitter

The SP160 splitter has a fail-safe mechanism which ensures the VHF has priority at all times. This means that whenever the power is cut to the splitter, it will provide direct access for the VHF radio to the antenna. This means the AIS is essentially disconnected from the antenna. As a result, it is recommended that the splitter be powered from the same power source (circuit breaker, fuse, etc) as the AIS and not from the VHF.

Or alternatively, and perhaps better, approach is to keep power supplied to it at all times whenever either the VHF or the AIS has power.