Re: Tips appreciated: Major frustration trying to pull cable through Mizzen.
Scott SV Tengah
On the back of the ICOM vhf unit at the nav station, on A54 #69, the yellow/green bonding wire is connected to the case, specifically the "ground screw". Therefore case is grounded. I am not sure if Amel did this on SMs.
The outer part of the PL-259 plug is connected to the grounding foil on the coax cable. If you solder/crimp one on your own, this will become immediately apparent. At the head unit, that connects the PL-259 plug -> coax foil -> head unit case -> bonding
At the antenna, on A54 #69, the male threads of the VHF antenna is mounted through a drilled hole in a horizontal "platform" at the top of the mast. The female threads of the PL-259 are obviously continuous with the male threads of the antenna. Therefore the PL-259 is then continuous with the mast and therefore the rigging. On the old Banten antenna, the male threads were isolated since the antenna and coax were one piece and presumably designed so that the male threads are isolated from the coax ground foil. That is not the case with any antenna that uses a PL-259 plug.
I don't think connecting rigging to bonding is a bad thing. Per Olivier, Amel started doing this on A54s in 2009; I have asked a few post-2009 Amels who have not changed their VHF to test for continuity between bonding and rigging and they have confirmed that it exists. Therefore, I don't mind it. As a side benefit, once I made the change, there was much less tarnishing on stainless above the deck.
2007 A54 #69