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Thanks Bill,

I came across this article on eham.. Might be of interest, it was written by
Paul KA6GEM....

""" The length of antenna wire is very important. The FC-40 will tune 160
through 6 meters as Yaesu claims but it is entirely dependant on the length
of the wire. Based on my findings, it will not tune a half-wave, a fairly
common limitation of "random wire" antenna tuners, and there doesn't appear
to be a single length that is ideal for ALL bands, although 37 feet, in my
experience, comes pretty close. One nice thing is that it is very easy to
change your antenna length: just add or subtract a few feet and that's it! I
have found that inserting a insulator at about 50 feet and leaving the ends
of the wires on each side stripped allows the option of simply connecting
them or disconnecting them to work the 160 meter band or perhaps the 60
meter band, etc.

I tried various lengths of wire from about 30 feet to about 130 feet, the
upper limit at my QTH. At 37 feet, I could tune up on almost every band but
the signal reports for the longer wavelength bands (80, 60, 40 etc.) were
marginal. As I increased the length of wire, I gained better performance on
one band but lost on others. At about 85 feet, I received excellent reports
on 40 meters, but then I could not tune on the 80 meter band as the length
was too close to a half wave.

I ran a series of comparisons with two dipoles, one for 80 meters and the
other for 40 meters. The 80 meter dipole performed better by one or two "S"
units than the FC-40 with a 65 foot quarter wave wire. I don't have enough
real estate to extend the wire to a three quarter wave or about 190 feet for
the 80 meter band.

On the 40 meter band, however, a length of about 90 feet performed very well
and the signal reports tended to be an "S" unit higher than the 40 meter
dipole. Although it's a vertically polarized antenna, I have not noticed any
major increase in noise with the FC-40 random wire as compared to a dipole.

Unlike the Icom AH-4, the Yaesu FC-40 will tune on 160 meters and I made my
first contact on the top band in almost 15 years with a wire about 85 feet
long. I had nothing to compare it to but the signal report I got was
excellent.

Although still fairly new, I have heard two other FC-40s on the air, mostly
in mobile set ups and both operators seemed very pleased with their
performance. In summary, I'm very pleased with this new automatic antenna
tuner. I'd give the Yaesu FC-40 a solid "5" (on a 5 scale) without
hesitation."""