[Elecraft] K3 0n motorboat

[Jim Brown]

On 6/9/2020 8:37 PM, Frank C Richards wrote:

> I also agree that all structures should be bonded to the counterpoise
> system.
> Some of the boat builders(Hatteras ,Bertram .etc) would put copper screen
> into
> the fiberglass layups of the flying bridge decks and roofs with a stud
> connected
> to it so that it could be tied into the system.

All good advice, to the extent that it applies to the boat in question. 
All the bonded stuff acts like more or less like the chassis of a 
automobile or pickup (except that lots of stuff on modern vehicles 
either isn't conductive, or those that are metal are often insulated 
from each other by paint). :)

> On commercial trawlers the antenna would be mounted on the mast about 30 or
> 35 ft above the water.It was fed with a wire about 25 or 30 ft long so it
> was
> actually a 55 or 60 ft end-fed.

That would be a pretty good antenna too. I would not recommend an HF 
antenna with an elevated feedpoint (or even an elevated current maxima), 
simply because there's some funny lobing in the vertical pattern that 
happens over water. The best way to feed a vertical on a boat is from 
the base, low, near the water.

> With the outriggers lowered and acting as radials, the trawl doors and
> cables in the
> water and everything else bonded together, it is a pretty good counterpoise
> system.

Yes. But remember that THIS question was specifically about a boat 
operating only on fresh water.

73, Jim K9YC