Gary Schafer wrote in
:


The diameter of the antenna wire is not too important. Actually the
larger it is the less resistive loss it has and less power will be
wasted in heat. But unless the antenna is significantly shorter than a
quarter wavelength that loss is negligible in the antenna as the
radiation resistance (radiation resistance is where the power goes to
be radiated) is usually much higher than the resistive loss of the
wire.

The diameter of the antenna wire is very important in the antenna's
BANDWIDTH. Go by the CG shore station and look at how WIDE the conical
monopole antenna is:
http://www.tpub.com/content/et/14092/css/14092_35.htm
The whole reason for the wide cone of these broadband HF antennas is to
make it look as if the conductor were several FEET across to the RF from
the feedpoint.

Multiple, parallel conductors are also used to increase antenna wire
apparent diameter in broadband rhombic antennas such as:
http://www.smc-comms.com/rhombic_antenna.htm

To quote the text:
"The simple one wire system has a bandwidth of approximately 2: 1, however
SMC have wide experience in the design of this type of antenna and are
able to offer arrays with 1, 2 or 3 wires per leg to give a bandwidth of up
to 4: 1 and, by careful design, gains of 22 dBi are possible."


However in a very short antenna the radiation resistance can be only
an ohm or a few ohms. Then the resistance of the wire would be a
larger percentage and the heat loss would be greater thus warranting a
larger diameter wire.

Huh?? ANY antenna under 1/4 wavelength long exhibits HIGHER and HIGHER
impedance the SHORTER it gets. The first low impedance of a wire antenna
occurs when its radiator (against a ground, artificial or real) is 1/4
wavelength long. A very short antenna, i.e. a 6' whip on the handrail, has
a very HIGH impedance as frequency decreases on the HF band. That's why we
use an L network to match it to 50 ohms....coil in series, cap to ground to
lower its impedance.


Otherwise a larger diameter wire has the advantage of greater
bandwidth for given tuner settings. But the difference between #10 and
# 16 would probably not be noticeable.

True, that's why we use multiple parallel conductors above.

As you well know, in the case of the ground system as we have said
many times before, it needs to be as short as possible or it becomes
part of the antenna and radiates. "The antenna starts at ground".
Anything above ground is antenna.


Actually, in a plastic boat, the radiation from the ground strap is useful
radiation. You've just moved the FEEDPOINT up the radiating element above
the sea. My feedpoint is about 4.8' above ground on Lionheart. It's
signal strength 5, readability 8 in Moscow, Belarus, UAE, Japan, Brazil,
most of Western Europe on 40 meters and 20 meters. Works pretty good!

73, Larry W4CSC