In article .com,
"Skip Gundlach" wrote:

As further background, we have full rails, with the gates combined
electrically with brass straps belowdecks, attached to the arch, the
pushpit and pulpit. We have about 110 lineal feet of 1" SS tube rail,
unless you count the inner rails, plus the arch. In addition we have
the standard 4" copper strapping leading to a sintered bronze Guest
plane below the boat, and also connected to a 3x5' plate under the
workbench top. I think we have a reasonably good ground.

You will never know if you have a "reasonably good ground", unless
you get yourself an Impedance Bridge, and check it at the frequencies
that you commonly work. Anything that is more than 12" away from the
water, isn't going to add "diddley-squat" toward building a Low Impedance
Wideband RF Ground System, and anyone who tells you otherwise, is just as
uneducated about MF/HF Marine Radio Antenna Systems, as you seem to be.
I have seen all kinds of Systems that looked very impresive, untill they
were evaluated with real insurmentation. 400 Sq Ft of Copper Screen in
the Cabin Overhead was proffered, as a really good RF Ground, by a well
known Boat Builder, 20 years ago. It didn't work any better than
having nothing at all, when tested, in a real radio enviorment. If
you got a Plastic Hull, you are NEVER going to get a Real RF Ground,
UNLESS the hull builder was smart, (they never are) and put 200+ Sq
Ft of screen under the gellcoat down by the keel. Cellulose hulls
are just as bad, and harder to retrofit that Plastic ones.
Like I said in my first reply, Autotuners were invented to allow any
"Dufus" to think he install an MF/HF Marine Radio System, and save
himself all that money he would have paid a Compitant Radioman.
SGC Autotuners are some of the worst of the lot, even if they did steal
the design from the real inventers. SGC couldn't even copy the design
correctly, and "Old PeeAir" couldn't design his way out of a "Wet Paper
Bag".

Me