That means your coax is not matched.
A simple, non invasive method to set up this circumstance is to start=20
with a long antenna, and trim small amounts while monitoring the current=20
flow.
I do not favor the method of using an odd-quarter wave length feedline.=20
Your antenna is still mismatched while your coax is happy.
A matching stub would probably be a poor choice in a marine installation.
You could also cook up a matching device which would be workable, but=20
the proper place for it would be at the antenna end. If the radio does=20
not match the coax it is broke.
The ARRL Antenna handbook remains my favorite antenna textbook.
I am inclined to believe that if you follow the manufacturer's=20
instructions and still have problems you have missed something. Usually=20
ground related.
Transmitters are certified by law.

If you are doing something not covered by normal operations, refer back=20
to the Antenna book. It was written especially for folks that push the=20
limits.
Do not forget that arcs and sparks are especially dangerous in Marine=20
operations and hampering the communications of others can change a=20
normal day into a front page disaster.

On 6/4/2014 11:24 AM, Joe McCauley wrote:
>   but there was a change in both dip frequency & amplitude depending on w=
here the coax was routed.

--=20
John Ferrell W8CCW

"Travel is fatal to prejudice, bigotry and narrow-mindedness=94
  Mark Twain


--=20
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