I put up an SAL-30 as well because it fit the space I had. Used it two
seasons...tried several minor changes but it never performed as advertised at
my site. Sold it to some contest station out west.
Cecil
K5DL
Sent from my iPad
> On Aug 1, 2019, at 1:32 PM, Lee STRAHAN <k7tjr@msn.com> wrote:
>
> Agreed Chuck,
> I maybe read David's post differently than he meant it to read also.
> This progression from TX antennas to loops to Beverages to 8 circle arrays
> is exactly how Hi-Z began. It is because the 8 circle is head and shoulders
> above all other choices at this location that Hi-Z Antennas even exists. Many
> different antennas have been tried here as well including loops and long
> Beverages. Many more comparisons have been made between different types that
> say under correct hardware application conditions and propagation conditions
> the best signal to noise reception for DX stations is with the 8 circles. All
> this says nothing about bang for the buck, real estate, or ease of
> installation which is a whole different way of looking at this.
> Where low angle DX is concerned I have actually measured the signal to
> noise ratio of signals from different receiving antennas and indeed at my
> location the best signal to noise reception follows the best RDF antenna. It
> may be true that a SAL-30 is appealing for other reasons but there is no way
> it would ever produce as good a signal to noise ratio on 160 meter DX signals
> as a properly operating 8 circle. Active or passive either one. The SAL
> antenna makes a great contest antenna as it has a wider beam width which
> hears more contest stations than the very narrow 8 circle patterns. Some Hi-Z
> contest users actually use both antennas so when a weak one comes along they
> switch to the 8 circle.
> I suggest ones that have not seen them to view Frank W3LPL's videos on
> receiving antennas. This is a very good presentation.
>
> Part 1 https://www.youtube.com/watch?v=RX4eLmJWNeo part 2
> https://www.youtube.com/watch?v=fyZR9uMBnIo
>
> Everyone's mileage may vary.
>
> Lee K7TJR
> Hi-Z Antennas
>
>
> -----Original Message-----
> From: Topband <topband-bounces@contesting.com> On Behalf Of Chuck Dietz
> Sent: Thursday, August 1, 2019 10:40 AM
> To: Rodman, David <rodman@buffalo.edu>
> Cc: topband@contesting.com
> Subject: Re: Topband: Which RX antenna is better?
>
> 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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