I agree with Mike and his comments about 40 meters.  Most yards, even small
ones as I have had in the past, will support a 40 meter inverted v without
much trouble.  I worked my first 160 countries using a wire inverted v on 40
that was less than 35 feet high.  Then one day, I purchased from a friend, a
rotatable 40 meter dipole.  I had up a 40 meter delta loop by this stage of
the game because I had a 65 foot tower.  I personally doubted the rotating
dipole for 40 meters would work or do any better but I was dead wrong.  I
kept the delta loop up for a couple of weeks and compared and there was no
comparison.  I have never, in all the years, and as many times as I had
tried, worked Europeans at sunset from here in Colorado with any wire
antennas I ever tried on 40 meters but with the rotating dipole, I did it
the first night I got it up on the tower and I did it regularly several
times every week.  It out performed anything up to that point that I tried
over the years.  I ran about 700 watts output was all, too.  Then I got a 2
element 40 meter beam and got it up at 70 feet.  Then I really started
working stuff.  I worked Europeans during CW contests at 2:30 pm in the
afternoon, Russians before sun set as early as about 4 PM during contests,
Africans about 3 PM, and a contest buddy told me to listen for Japan long
path beaming over South America during the contests because sometimes they
came in.  I did and worked my first Japanese long path beaming Southeast.
Further more, with the rotating dipole, I began working some long path,
beaming to the southwest, some mornings.  Most were northern Europeans.
Once I got the 2 element beam, however, I worked many 40 meter long path
stations beaming to the southwest in the mornings clear down in southern
Europe such as Italy, Chech Republic, Austria, and the like.  A rotatable
dipole on 40 isn't all that big and any rotator can handle turning and
breaking it just about.  I had a tri band 30, 17, and 12 meter rotatable
dipole for a few years, too, and found it just as superior to the wires I
had been running on those bands.  The nice thing about the single element
rotating antennas, you don't have to turn it much, that is, all the way
around, to get a peak on the guy who you are working.  I was, on the other
hand, always cranking my 2 element 40 meter beam around.  I have likewise
run ground mounted and roof mounted trapped verticals and had very good luck
with them on 40 meters.  Not as good of antenna as the 40 rotatable dipole
but good for what it is.  Just some further comments on the topic.

Phil.
K0NX