The pattern null depth off the ends depends on antenna height.
At 1/4 WL (35 ft on 40M), there isn't much pattern.
At 1/2 WL (70 ft) and greater, there is a discernable
pattern which varies with takeoff angle.
For more detailed information, I suggest your model a 40M
dipole at 35, 50, 70, and 100 ft and look at the resulting
patterns at 15, 30, 45, and 60 degrees at each height.
A 40M rotary dipole is a very effective DX antenna
when mounted at 70 ft or higher. Even 50 ft is useful,
but in this case, higher is better.
Tom N4KG
On Tue, 16 Apr 2002 Ronald KA4INM Youvan <ka4inm@tampabay.rr.com>
writes:
> > YES! I recommend it highly. A 40M rotatable horizontal dipole
> is a great antenna.
>
>
> I have always heard: `80 & 40 meter dipoles have such small nulls
> that the
> direction there orientation is not important,' and I have been told:
> (about 40 meters)
> `you can talk to any place in the state, no matter how your dipole
> is oriented'.
>
> This seems to be true with my 40 meter dipole. I can rag chew
> with my chum in NC
> from FL with our antennae at crossed orientation (with my 45 watts)
> like locals.
> (as well as with him using a vertical)
>
> What does the rotable of a 40 meter dipole get you?
>
> (I am just asking, I am not trying to start a fight.)
>
> 73 (= Best Regards) de: Ron ka4inm@tampabay.rr.com
> 100% LINUX, 100% of the time. SENT Time and Date are UTC
> Visit my HAM Web SITE at: http://www.qsl.net/ka4inm
>
> _______________________________________________
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