Well Bruce/Me, I think you need to pull your two "selves" together! 
 
Sifting through the humorous postings, I think your bottom line is that 
HF/MF vertical antennas will not work well (sometimes I think you mean 
will not work at all) unless they are (1) over sal****er with a return 
path capacitively coupled to the sea (at least for nonmetallic vessels); 
or (2) over land with 100 quarter-wave radials in marshland. 
 
You have labored to persuade us that less-than-perfect marine RF ground 
systems are certain to disappoint. 
 
It will surprise you, perhaps, to learn that there are many thousands of 
vertical HF and MF transmitting antennas in operation in the world today 
that satisfy none of those conditions, and yet enable effective 
communications activities. Some on land and some over water. These 
installations are supported by rigorous theory as well as by on-the-air 
performance data. 
 
If you would like to learn more about how this is being done, often with 
losses of only a few dB below ideal conditions, drop in at 
rec.amateur.radio.antenna and "read the mail." You'll find some 
bombastic assertions and opinions to be sure, but also many reasoned 
analyses and even quantitative experiments. Hope to see you there, Bruce. 
 
Regards, 
 
Chuck 
 
 
 
 
 
 
 
Bruce in Alaska wrote: 
 In article , 
  Me  wrote: 
 
 
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 
 
 
 Geeze Louise "Me" give the guy a break......  He was just asking for 
 an opinion.... 
 
 
 Bruce in alaska 
		 
		
		
		
		
		
		
		
		
	
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