For use in salt water, a number of Cu alloys have "excellent" corrosion
resistance. Among those that are available are the Admiralty Brasses
(C44300 with As or C44500 with P). They have about 25% conductivity wrt to
soft Cu. (Brass is mostly Cu and Zn.)

Phosphor Bronze (C52100) is also a candidate with 13% conductivity.
This is particularly good for antenna wire use.

Pure Cu is expressed as having "good" resistance.

Find a thin plate of Admiralty brass and bond Cu or phosphor bronze wire
to the plate. Put the assembly into the water as "ground" and you are done.

73, Mac N8TT
--
J. Mc Laughlin; Michigan U.S.A.
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