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From: Michael Lahrkamp (no email)
Date: Thu May 17 2007 - 10:51:55 EDT
I know I'm gonna get a rap for this: In my opinion, HF is primarily used
for long range communication - getting weather, etc. Seems to me the
whole situation regarding antennas and the like gets eliminated when
considering satellite communications as an alternative to SSB/HF and
what's rapidly becoming antiquated technology. Still, lots of boats have
HF and having used both, the sat phone makes life so much easier (and
more reliable for me based on my last ocean passage). No cutting rigging
or holes in the hull, no large power draw, no tuners or ground planes
and no licensing. Leave it on all day and it rings when someone is
trying to contact you. Every crew member who's ever used a cell phone
would intuitively know how to use it. They're small and portable so you
can take it with you into a life raft should the situation arise. Low
cost to acquire but there is a cost per minute usage. :-(
Anyone else have some thoughts? Maybe a new thread?
Cheers,
Mike
Soul Healer, B411, Toronto, Canada
________________________________
From:
[mailto:] On Behalf Of Bryan Genez
Sent: May 17, 2007 10:29 AM
To:
Subject: Re: [world-cruising] Re: ssb antennas....
On 5/17/07, Donald Smith < <mailto:donsmith%40att.net> >
wrote:
>
> Friends,
>
> Every time one cuts a cable and inserts a mechanical splice (i.e., an
> insulator) a potential failure point is introduced to the system. No
> matter how one tries to rationalize that mechanical connection an
> additional potential failure point has been added. That's a fact!
> If one can avoid potential failure points then that is prudent.
> That's fundamental engineering.
>
> Of course an insulated backstay works well as an antenna. So does
> just hoisting a piece of wire from a halyard. So does the split-lead
> antenna for GAM. The fact is that on a sailboat the counterpoise
> (RF ground) has more to do with the efficiency of an antenna than the
> antenna itself (assuming adequate length, insulation, and tuning).
>
> So, make your antenna choices as you will and SSB to your hearts
> delight.
>
An element of fundamental engineering is the science of making
attachments
that will stand up to their environment. The reality is that the failure
rate of backstay insulators is ridiculously low. I know of only one in
the
past 25 years, and that was because the insulator was not attached
properly. Most boats that I've seen have potential failure points far
more
likely to fail than a insulated backstay. Most of these potential
failure
points were designed-in by the builder.
The backstay antenna has the advantage that it can be used while
underway or
in heavy weather. Most other antennas will not work under those
conditions.
Another alternative that I've been told works is the "Outbacker" - a
clamp-on vertical antenna that does not require a tuner. A web search
will
turn up specifics.
-- Best, Bryan Genez "Capella" V40-158 New Bern, NC [Non-text portions of this message have been removed] [Non-text portions of this message have been removed]
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