Cecil Moore wrote in message ...
Mark Keith wrote:
I was so disgusted with the things after
the 2nd FD, I refused to ever use one again. And I haven't. I bring my
own wire and coax just to make sure I don't get stuck on one. And I
wasn't the only one complaining either...
I won't be suffering with a system efficiency in the mid 90's...

It would be easy to try my G5RV modification. For 3.8 MHz, it is
25 ft of "450" ladder-line with a 1000 pf cap in parallel at the
ladder-line/coax junction. I wish you would open your closed mind
and try it sometime.

I don't have much use for one, even if I wanted to. I'll never dump my
dipoles to change to a G5RV. I'll never use an antenna system with a
coax/choke/ladder line feed either. Sorry...But feel free, if you want
to...

I guess this is what led me to question your choice of the perfect FD
antenna. 80m, being the band of real issue.

A perfect FD antenna would allow one to change bands relatively
quickly without sacrificing performance. My G5RV does that.

The only bands I work at FD are 80 and 40 CW. I use parallel dipoles
at right angles. My band change is instant. If for some reason I get a
wild hair, and decide to try 20, I get on the beam. I never go any
higher than that, because it's always night when I operate. I don't do
anything in the daytime except set up my junk, and then lounge around
and look useless for a while....:/ I then go home, and come back later
in the night and operate when it's cooler.

The 110 ft dipole that I came up with has an SWR of less than 1.7:1
over the entire 75-80m band. That sure beats the bandwidth of a
resonant coax-fed dipole.

Who cares if I don't move more than 100kc all night? I zig zag back
and forth from 3500 to about 3600...7000 to about 7075 on 40..



That's not the old wives' tale. The old wives' tale is, "A G5RV
is a terrible antenna that cannot be improved to near perfection."
With minor modifications, a G5RV will compete favorably with any
other HF dipole on any HF band.

I guess your idea of "near perfection" is different than mine...I
agree it can be improved quite a bit, but I'll reserve comment on the
"near perfection" part...
If I wanted a multi band dipole using only one element, I would use a
80m dipole, with insulators at each point, for each band. I then use
jumpers to bypass whichever insulators I want for a certain band. I
prefer that method to yours because the feed stays at 50 ohms appx,
and the pattern is a normal dipole pattern on any band I use. To me,
this is more "perfect" than your method, as it retains my preferred
"50=50=50" policy.
But it's all personal preference...Below would be a 80/40/20 version,
which also works 15m on the 40 leg. I've used this method many times.


o-----------------o----------o----------00----------o----------o---------------o

But for what he originally wanted as far as covering two parts of 80m,
with one antenna, I still would prefer paralleled dipoles, cut for
each section of the band. I would run them at right angles like a
turnstile. The SWR curve will look like a "W". Solves his problem, and
is still ultra efficient with no caps to diddle, weird feedline
combos' etc..Add 40m legs, also in parallel, and it's instant
bandchange between both parts of 80, and also 40. Won't have to do a
thing except dial the radio around...I think he said he's already got
the high bands covered...To me, thats the "perfect" antenna for his
problem, and what I would run in his case. But to each his own I
guess... MK