Hi Ling and Michael,

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

I have to admit that I have no direct experience with large HF vertical
antennas (which, as Michael did, I assume you are talking about). 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.

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.

Sean

At 09:40 AM 2/20/2003 -0600, you wrote:
>Resent due to OE tag stripping, sorry I haven't caught on yet.  ;-)
>
> > Hi RF Jim, Sean and all,
> >
> > Can someone introduce me to any good sites for antenna grounding?
>
>The ARRL Antenna book is probably the best document available.
>
> > The problem with the system that needs fixing I think is with the
>radial
> > ground network.  The antenna is installed in a small island. The
>radial
> > wires go into the sea, strong waves and current entrangles the whole
>network
> > and breaks the wires.  When this happens, the reflected power rise to
>50%of
> > transmitted power and tripped the transmitter.
>
>I take it this is a large 1/4 wave antenna for low frequencys.  You
>won't get a ground plane much better than the radials in sea, but you
>can use an LC network to match the transmitter (actually the feed line)
>to the changing impedance of the antenna.  This will make the
>transmitter much happier, but it won't make the antenna work any better.
>
> > Is any other method of grounding (without needing to extend into the
>sea)
> > that might solve this problem?
>
>Not that I am aware of.  :-(  Maybe you could use copper pipe instead of
>wire?  Outside of that, the only thing I can think of is to switch to an
>antenna system that doesn't need a ground plane  e.g. a dipole.
>
>michael
>
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