AIS Antenna or Splitter and Axiom 12 Goof

I'm working with John and Kim on their new Leopard 45, GypseaBLU, with some electronics installation and have a couple of tips to share.

Raymarine Axiom 12 Chartplotter Chip Goof

The chart chip socket on the Axiom 12 (not the Pro model) has a small space above and below it where the case fits around it. It is easy to insert the chip into one of the spaces instead of into the chip socket. These spaces are just the size of a chip, so it seems like you're inserting the chip correctly until it doesn't click into place. It seems that missing the chip slot is a common problem. World travelers who need to regularly access and update the chart chip may want to invest in the Axiom 12 Pro or in the Remote Card Reader. At a minimum, be very careful in inserting the chip. A simple fix to prevent this goof is to add a bit of caulk around the perimeter of the chip socket. But on the late model L45's access to the back of the chart plotter is challenging, so a better solution may be the remote card reader. You don't need to ask how we learned this tip. 😞

AIS Antenna or Splitter

We're installing the Raymarine AIS700 transponder. There is a new AIS Class B+ standard that uses a 5 watt transmitter and the same transmission protocols as are used by Class A transponders. Raymarine doesn't yet have a transponder that supports this new standard (very few vendors do as of  Nov 2019).  The AIS700 incorporates a splitter, but we were prepared to install a separate AIS antenna. A bit of searching on the subject found an in-depth analysis of the various tradeoffs: AIS Overview and Installation Considerations. Another good article is VHF‐AIS masthead antenna and coax installation, selection, and test. The end result of this analysis is to use a good quality coax and that height is more of an advantage for distance than having a separate antenna. Note that VHF antennas should not be placed within 4 ft of another antenna or of parallel metal objects like masts and shrouds. These metal objects result in signal propagation distortion that can result in reduced distance in certain directions. So a masthead installation is better than a solar arch. A spreader installation is affected by the mast and shroud. Two antennas on the masthead affect each other.

We opted to go with the built-in splitter, since it has low insertion loss.

  -Terry