> > I'm flattered to be included in the list of "RF experts" ;-) (Of
> course, assuming I'm the Sean you are talking about!)

You should be :-)

> However, from what I do know, I like Michael's suggestions: either make
your
> radials more robust or use an antenna type that doesn't require them.

The antenna sits at the end of a narrow (2m wide) concrete platform, the
platform is on a 45 degree-slope rock (sea-bank).  Using pipe is an
interesting idea, might have to test it out first.  Think about it, pipe
might suffer a greater force from the water-movement than wire as its
surface area is larger.  They would have to bolted even more tightly.
Perhaps the problem is the wire are bolted too lossely.  I am no structure
engineer but have to second-guess their work now.

> AFAIK, theres really not much else that he could do.  ;-)
> > What kind of soil do you have on this island? It might also be
> possible to just place the radials in the ground, but probably not if it
is sandy.
>
> AIUI, the radials don't actually have to be in contact with earth ground
> to still function well.  He could spiral the radials around so that they
> are not so far into the sea and this should work nearly as well, as the
> electrical length of the radials would still be the same.  He may have
> to tweak the matching to the antenna though, since nearly anything that
> he does will have some effect on the feedpoint impedance and possibly
> the radiation pattern.  I'm a bit rusty on my antenna theory, as I'm
> sure you can see.

There is an Antenna tuning unit (ATU) then do the matching.  We found out
that if the ground (if we are right) is no good, the transmitter tripped
faster with an ATU than without.

Could you tell more about "spiraling" the radials?

Thanks for respnding.  As usual, please shoot freely.

BR, Ling SM

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