Your results of the order of performance of these antennas are somewhat
different than other, published results. I wonder if the composition of
your ground would have something to do with that? Good or poor soil? Also,
how long was the Beverage?
I have a SAL-30, which is by far my best receive antenna since I had to
take down my Beverages, but my take away was the Beverages beat the SAL-30
most of the time. This is over medium to good soil. I would have expected
the 8 circle to be better than all the others at least 90% of the time. (At
least over good soil.)
I have been pondering which receive array to put up in a new location with
plenty of room, so I have been looking at this.
Chuck W5PR
On Thu, Aug 1, 2019 at 11:19 AM Rodman, David <rodman@buffalo.edu> wrote:
>
>
>
> This is possibly a more complicated subject than just performance. I gave
> a lecture on this topic, comparing a Hi-Z circle 8, SAL-20, SAL-30,
> beverage (unidirectional and bidirectional and BOG) and the K9AY array.
>
>
> In this talk, I considered performance as a factor, but also considered
> maintenance, size, mechanical stability, cost and ease of construction and
> installation.
>
>
> All things considered, the top 2 at my QTH were the Hi-Z circle 8 and the
> SAL-30.
>
>
> Here is a quick summary of my findings.
>
>
> Circle 8: highest cost, most complex to install and construct, requires
> large footprint of land, best of all antennas as it requires almost NO
> maintenance and performance second overall to the SAL-30.
>
>
> SAL-30: modest cost, modest install and construct, modest footprint,
> requires minimal repairs (usually to the coupler wires) but overall
> performance best of all for directionality and gain.
>
>
> SAL-20: modest cost and somewhat simpler than SAL-30 to install and small
> footprint. Performance almost identical to the K9AY array.
>
>
> K9AY: modest cost but slightly more complex to construct as compared to
> SAL-20 and about the same size. Performance less than SAL-20 due to fewer
> directions.
>
>
> Beverage unidirectional: mechanical stability good when constructed with
> copper coated steel wire #14 or larger. Gain fine when desiring only 1
> direction. Depending on the location may be placed in half a day from
> start to finish.
>
>
> Beverage bidirectional: mechanically unstable when constructed with
> commercial products using either RG6 or twin lead. Requires frequent
> repairs due to fatigue or failed connections. Performance overall is not
> on par with other directional arrays.
>
>
> BOG: simplest of all antennas to construct, install and maintain. Can be
> installed in an hour or two. Should be unfolded at spring time each year
> to keep wire from being incorporated into lawn. Convenient when only 200'
> available. Can be band specific.
>
>
>
> Just a quick summary. My location does not lend itself to beverage
> construction. about 2/3 of my 25 acres are heavily and complexly treed with
> brush so overgrown that it can be a chore to do almost anything for
> installation or repair. This is why I prefer the SAL-30 overall. The
> circle 8 took me one summer (as my only project to install) by the time the
> land was cleared, site measured, antennas constructed and all the coax
> installed. The trade off is that this antenna has been the most
> mechanically stable of any antenna that I have ever had.
>
>
> ---
> David J Rodman MD
> Assistant Clinical Professor
> Department of Ophthalmology
> SUNY/Buffalo
>
> Office 716-857-8654
> _________________
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
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