Gordon Wedman wrote:
Hi Chuck
I kind of suspected that it would only work well over a limited frequency
range and that the typical antenna tuners would not help. Thanks to Doug
and yourself for confirming this. I'm not planning on installing one as I
have a conventional backstay arrangement but I was just wondering if anyone
actually used this kind of setup as I'd not seen it discussed.
I guess if you are a Ham and tend to work only one band this might be a good
arrangement for your boat.

"chuck" wrote in message
...

Hello Gordon,

The 20th edition of the ARRL Antenna Handbook has some information on a 40
meter, masthead half-sloper as you described. You might find that
interesting.

As Doug mentioned, this is basically a single-band antenna, except that it
would probably work ok on odd harmonic frequencies. And it would very
definitely radiate on other frequencies in an emergency, provided you used
an appropriate tuner.

Good luck!

Chuck












Gordon Wedman wrote:

Over the holidays I killed some time looking through a few back issues of
Cruising World. In the April 1986 issue a boat-based ham operator said
he used a top-fed backstay antenna with excellent results AND he had no
in-hull ground plane. He said he connected the shield from his feed wire
to the mast-side of the backstay and this allowed the mast and all the
standing rigging to act as a ground plane. He didn't say anything about
using stand-offs between the feed wire and the mast. I would think you
would get a lot of signal loss over that much length if you didn't use
stand-offs?
If a person could put up with the appearance and make sure the whole
set-up didn't get torn down by sails/running rigging, would this really
give good performance? I don't recall reading about this type of set-up
so I guess its not too common on recreational boats but maybe it could be
worth considering in some situations

I think it's a great idea. If you tune to some "off" freqs, you
could try orienting the AE different ways by turning the boat. You
may be surprised to find directivity nodes here and there at certain
freqs.

I have often wondered why I don't get a ham set, or even a decent
receiver, so I can fool around with some weird AE Ideas. How about a
loop using the fore and back stays, insulated at the top, a balanced
twinax feed and connected from fore peak to transom by an insulated
bilge wire on spacers away from the bottom of the hull?

Alternatively, my mind says "Why not feed at the centre of the
bilge lead, or even off centre, and maybe not bother insulating the
stays at the top?" The shrouds would not be connected to anything
at the chain plates.

I suspect directivity trials could yield a neat plot showing odd
peaks and strange directivity. Some of those nodes may be surprising
and even useful.

Loops are particularly quiet on Rx. Ever try one for Tx?

Has anybody actually done any of this wierd stuff?

It seems to me that some software should be able to predict all
this. Anybody know?

Terry K