Brian Kelly wrote:
Cecil Moore wrote:
Denton wrote:
I picked up a used one last sprng, set it up about 3 ft off the ground in
the back yard...and took it back down within a couple of weeks.
Signals were way down compared to my 450 ohm ladder line fed 80 meter
doublet on all bands.

I had the same experience with a 1/4WL 40m vertical. Now I wish
I had run some A/B transmitting tests as well as the A/B
receiving tests

I thought you did that with N2EY . . ?

We did. From Cecil's QTH in Texas to mine here in suburban Philly I
could hear no
significant difference between the two antennas in A/B tests where I
didn't know
which antenna was being used (just A versus B).

But that's just one data point on one band over one path.

which the vertical flunked mainly due to an
extremely high noise level.

I did some of that sort of A/B testing between an elevated 1/4 wave 40M
GP and an 80/75/40M 130 foot end-fed inverted L a number of years ago
and the GP did not fare well at all. As it happened there wasn't much
of an electrical noise problem in the neighborhood then so QRN one way
or the other was not a term in this specific equation.

The vertcal leg of the inverted L was spaced about 20 feet from the
tower and was base-fed by a remotely controlled L/C tuner out in the
back yard, a USN surplus gun director selsyn motor cranked a big rotary
inductor which allowed me to QSY from 40 to 80/ 75. But the process ate
a minute or two to do which was a pain in the tush during the DX
contests I was into. Instantaneous band changing in that game matters.

The apex of the L was around 60 feet AGL. The 70 foot "horizontal" run
sloped down from the apex to about 35 feet AGL. The L worked quite well
on both bands, I could snipe JAs at will with just an SB-200 on either
band from here on the east coast when band condx were decent.

I decided that I had to put up some kind of 40M antenna so that I could
quickly QSY from 80/75 to 40 by simply flipping an antenna selector
switch which would get me away from the increasingly annoying "twist
the selsyn 30 turns" routine when band swapping.

So I built a textbook-classic 40M 1/4 wave GP which had a
self-supporting 35 foot +/- radiator. The base was at 35 feet AGL,
there were four downward-sloping wire radials. The whole thing perched
atop the roof of the abode. SWR over the entire band was essentally
unity.

Turned out to be a complete waste of time, money and effort. For
whatever reason or reasons there wasn't much difference in received
signal strength levels beteen the two antennas when I was listening to
long-haul DX like JAs and VK/ZLs on my end. But when I called them more
times than not they did not come back to me. I spent a couple intense
very early morings A/B swapping between the L tuned for 40M and the GP
QSOing the DX. In 90% of the cases they "heard me much better" when I
was using the L than they did when I used the GP. I took the GP down
and good riddance.

I'll leave the theoretical howcums of my experince to those of you who
are deep into the physics of electromagnetics. For my part another 1/4
wave HF GP just ain't gonna happen here again elevated with radials or
ground mounted with gazzilion radials.

I think the differences were two:

First, the ground plane with four radials wasn't all that hot, and the
lossy house was in the near field. The L wire was high-Z and its ground
wasn't all that important. Plus the ground was high conductivity moist
Aldan soil.

Second, the part of the GP with the most current, and therefore doing
the most radiating, was the bottom part. I don't know how high the
house roof was but it couldn't have been much more than 30-35 feet?

But the L wire on 40 meters was a full wave. High current was halfway
up the sloping part, and about halfway up the vertical part.

So you probably had less ground loss and some serious polarization
diversity. End result: they heard you better.

. . . half-wave verticals being a whole different ballgame . .

I'm thinking about putting the
vertical back up as a 1/4WL 30m vertical fed at the base with
an SGC-230 that I already have. Such an antenna should work
pretty well on 40m-10m, at least for transmitting.

Go for it and post your results.

Agreed

73 de Jim, N2EY