While I don't know much about the properties of kevlar, electrical or
physical, if it has good electrical properties at the RF frequencies
involved then it should work ok.

As far as wrapping the wire around it, I would use a very long wrap.
Not many turns. While more turns will probably make an excellent
antenna for the low frequencies, 2 and 4 mhz, it will hinder the
higher frequencies. The coil will act as a choke at the higher
frequencies and not allow them to pass. It will effectively make a
rather short antenna at the higher frequencies.

When the old 2 mhz marine antennas were made they had a wound coil in
the fiberglass whip. It performed much better on 2 mhz than a straight
whip with no coil. But it was next to useless on frequencies above 4
mhz as the coil effectively disconnected the upper part of the antenna
on the higher frequencies.

With the higher frequencies in common use now you will never see one
of those loaded antennas in service anymore. Unless it is a dedicated
2 mhz antenna and there are other antennas for the other frequencies.
That is the best of both worlds.

Regards
Gary


On Sat, 12 Jun 2004 12:05:08 -0700, "Max Lynn"
wrote:

I am the one who posted re the kevlar backstay. I implemented it and used
the setup on a recent Mexico trip. I can only tell you that my rig was
probably the best in the fleet of several boats. A lot of racing sailboats
are switching their rod or wire backstays to Aramid at this time. The
weight savings is dramatic, and the cost is roughly half of what a backstay
with insulators would cost. It's interesting that with all the expertise on
antennas in this group none sees fit to answer your original question, but
rather they choose to critique a proven rigging advance.


"Steve (another one)" wrote in message
...
Dear all

May I pick-up on something mentioned in response to my earlier question.

It was suggested that running a wire up a kevlar backstay is a simple
soultion and avoids having to insulate a piece of conventional rigging.
This sounds very sensible to me and plan to try it, it avoids having to
mess with exposed connections to a wire backstay.

However then Bruce in alaska said:
Then just helical wrap the antenna wire
around the Kevlar Backstay and have a really nice "Fully Loaded
Antenna
with alot of electrical length......

Could someone (Bruce perhaps?) explain this. Would I gain performance by
simply wrapping the wire ? Is no of turns per length of backstay
critical ? Is 'core' diameter critical ?

Thanks

Steve