As I noted on June 7th, I decided to switch the new amplified Splitter in parallel with the VHF, Stereo, and AIS. This way when any one of the three was switched on, the Splitter would be as well. The SP-160 would still be still fuse protected between the junction of the three red parallel wires and splitter. Well after I redid the circuit diagram in the morning, I realized there was a sneak circuit created by this arrangement — the breaker for any protected device would now power up all three protected devices. What was needed was a Double Pole-Single Throw switch for each device, something I had neither room for nor interest in adding. Instead, I connected a DC/DC Solid State Relay to all three breakers. Now switching on a breaker energizes the relay and it switches on the Splitter — and only the device the breaker is intended to protect.
Unfortunately, the installed AIS is too blocked by other equipment for the internal GPS antenna to work (in an hour it found one satellite and lost it in less than minute). So now the optional antenna must be installed. More buck suction.