Dave, I actually use a very long run of ladderline at my quite windy
QTH. I'd estimate that it's about 250' long and V-shaped to allow me to
come away from the doublet at a right angle. The line is fastened to
lengths of 4X4s that I've sunk in the ground along its route and I use
bungee cords fastened to other 4X4s at several points to prevent it from
blowing into the trees. It all works quite well.
73, Joe
David Gilbert wrote:
> Yes, the EDZ is a very nice configuration and it sounds like you have a
> nice setup. I'd be tempted to try the same thing myself for 80m and
> 160m except that the long ladder line would have too large a surface
> area for the wind gusts we get here.
>
> There are ways to make a "single" antenna work better on multiple bands,
> though. I normally dislike fan dipoles since most people cut each
> section for resonance on a particular band and they get all sorts of bad
> patterns as a result, but with a tuner you can choose the segment
> lengths so that none of them are resonant on any band and the patterns
> for each stay pretty good. Two non-resonant dipoles in a fan
> configuration should decently cover 40m and above, and three would
> probably give 80m as well. I'll try to come up with some lengths if
> anyone is interested.
>
> Dave AB7E
>
>
>
> Joe Giacobello wrote:
>
>> Agreed, but there's a lot to be said for getting on all bands with one
>> piece wire even if the radiation pattern is not optimum for a
>> particular direction. They're tough to beat for a general purpose
>> antenna. Obviously, if one has options for multiple antennas, phased
>> arrays or rotatable directional antennas, they're the way to go.
>>
>> I currently use an 80M EDZ fed with balanced feed line on 40, 80 and
>> 160M. On 80 I get 3 dB gain broadside vs a dipole, and on 160M it is
>> effectively a dipole. On 40M I use it to get omni-directional
>> coverage, more or less, for a weekly 40M SSB net.
>>
>> 73, Joe
>> K2XX
>>
>> David Gilbert wrote:
>>
>>> That's true to a point. I have used efficient homebrew antenna
>>> tuners my entire ham radio life and wouldn't be without one. But you
>>> can get some REALLY ugly radiation patterns from trying to use the
>>> same antenna on several bands. The antenna may tune fine and still
>>> not be putting your RF even close to where you want it to go. I
>>> always tried to stay reasonably close to a half wavelength ... for
>>> example, using a 50 foot dipole for both 20m and 40m still gives a
>>> fairly clean pattern on both bands.
>>>
>>> Dave AB7E
>>>
>>>
>>> Donald Chester wrote:
>>>
>>>
>>>> The best way to solve the problem once and for all is to feed the
>>>> dipole with open wire tuned feeders, using a balanced, link-coupled
>>>> antenna tuner. That way you can instantly change the resonant
>>>> frequency of the antenna to any spot in the band from the comfort of
>>>> the operating position. And one dipole can cover multiple bands
>>>> without traps or other jury-rigging.
>>>>
>>>>
>>>> Don, k4kyv
>>>>
>>>> _______________________________________________________________
>>>>
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>>>
>>>
>>
>
>
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