Re: Ssb grounding voters poll......
The first choice would be to, if your vessel has keel coolers, attach the ground from the tuner to them. If you do not have keel coolers by far the best alternate solution would be a ground "plate" such as a"Dynaplate" or equivalent block on the outside of the .
There are 100 and 1 other ideas out there however after spending in excess of 40 years in the radio communications business I have determined that there are really only these two ways that "really" work.
I have seen installations where the radio ground was attached to the engine with the shaft coupling strapped to provide continuity so that the shaft and prop were the "ground" and others where there was a sheet of copper attached to the hull interior, below the water line, as a ground plate and others where the radio was connected to the vessel bonding system.
While these sort of worked they could be improved upon drastically by temporarily hanging a hank of about 100 ft of bare wire over the side, connected in addition to whatever existed for a ground.. This is a good test for any existing ground system - quick and easy.
Any ground system should be connected via a good grade of capacitor such that there is no DC conductivity to the ground system thereby reducing the chance of stray current paths.
On our wood hull trawler with keel cooling I use the coolers and with an identical radio set up have communicated, on the ham bands, with most points of the world from the Pacific Northwest and even trailing about 300 feet of bare wire overboard did not make any improvement over this existing system.
John Tones MV Penta