[Elecraft] antenna farm

[Duncan Carter]

Duncan Carter wrote:
> Even if you don't have space for a large radial field, you are apt to 
> do better with elevated radials, even one "radial" ( the lower half of 
> the dipoles) as I have.  Putting wire in or on the ground is mainly 
> useful for keeping earthworms warm.   To read a lively debate on this 
> subject which includes links to two excellent technical references, 
> see all three pages of:
http://www.eham.net/forums/Elmers/237953

73, Dunc, W5DC
>
> Bob Cunnings wrote:
>> And, if you don't have enough space for a radial field on the ground,
>> try a vertical doublet, center fed with balanced line for multi-band
>> operation. I've been using one for years which is 32 ft. tall and can
>> be loaded easily from 30 meters to 15 meters. Much better for dx than
>> my low dipole and the elevated feedpoint (at 16 ft.) seems to help
>> overcome ground clutter (enclosing block walls etc.). The wire is
>> supported by a 32 ft. telescoping fiberglass pole, with footprint less
>> than one square foot!
>>
>> Bob NW8L
>>
>> On Mon, Dec 14, 2009 at 12:58 PM, Ron D'Eau Claire <ron at cobi.biz> wrote:
>>   
>>> As Ken mentioned, height is an important factor in a horizontal or
>>> semi-horizontal antenna. There's limited "gain" in any direction at low
>>> angles unless the radiator is 1/2 wavelength above ground. That's why most
>>> of us have to live with little directivity on the lower bands.
>>>
>>> The option is to consider verticals. Unless you are living on salt water (or
>>> atop a sheet of copper), or can make the vertical a full 1/2 wave high, the
>>> vertical won't be as efficient as doublet or dipole, but a vertical will
>>> produce typically much better signals at lower angles of radiation than a
>>> horizontal antenna (under 1/2 wave high) and doesn't require a huge
>>> 'footprint'. Also you can phase multiple verticals for directivity and even
>>> design them so you can use them for supports for horizontal wires on the
>>> higher bands.
>>>
>>> You've probably noticed that 45 foot verticals are being heavily promoted
>>> these days. That's an old design that is very handy for limited space. It
>>> provides low angles of radiation on all bands up through 20 meters where
>>> it's 5/8 wavelength high (on bands where it's more than 5/8 wavelength the
>>> angle of the main lobe rises from the horizontal and minor lobes appear at
>>> high angles). Down on 80 meters it's just a bit shy of 1/4 wavelength. With
>>> a good ground system it can produce excellent results down there and even on
>>> 160 - especially when compared with the short, low (in wavelengths above
>>> ground) antennas most of us are forced to use on those bands
>>>
>>> Ron AC7AC
>>>     
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>