Copper foil for SSB grounding

[rszemeti]

I had researched this fairly thoroughly and the conclusion was that it should be 75 mm x 3mm thick; braid was not advised for RF.

I have a steel boat and don't want a great length so I think I will have to go with lightning conductor strip (and insulate it) as a

That sounds ludicrously over the top. A simple piece of 4mm earth cable would be more than sufficient and on a steel boat, almost entrirely superflous!

You need to remember that the effective impedance (in RF terms) of your ground system is going to be in the hundreds of ohms, any rudimentary piece of cable is going to have an impedance of less than an ohm, so will make an insignificant contribution to the overall impedance of the counterpoise/earth.

To be fair, I have seen copper strip of that size used in an RF installation ... but that was when I worked as an Engineer with the BBC, and it was on the 500kw transmitter at Droitwich.