ARLA/CLUSTER: BOLPA-10 Press Release - InnovAntennas - For CT Press Circulation

[João Costa > CT1FBF]

Em 06/11/2016 10:35, "Antonio Matias" <ct1ffu  gmail.com> escreveu:
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> Hi Tony,
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> Could you please circulate to the CT press?
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> Hockley Essex, United Kingdom – InnovAntennas Limited, The premier
supplier of sophisticated and Innovative directional antenna systems
announces today the release of a game changing HF multiband directional
antenna; the new Band Optimised Log Periodic Array (BOLPA).
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> The first in the series of BOLPA Yagis provides exceptional performance
on 5 HF Ham bands simultaneously form a single feed point so is ideally
suited to the modern-day SDR radios such Apache Labs, Flex Radio Systems
and Expert Electronics where multiple band receiver slices can be used at
the same time.
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> What makes the BOLPA different to traditional Log Periodic Arrays (LPDA)?
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> The BOLPA is a result of 2 years’ worth of development and testing.
Justin Johnson G0KSC embarked upon a project to test the monoband abilities
of a log periodic. It is known that an LPDA in traditional form can provide
usability over a very wide range. However, the compromise being performance
in terms of gain and Front to Back (F/B) are generally average to poor.
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> The project started with Justin optimising a 3 element LPDA for the 20m
band only. This produced an antenna with a very short (6’, 1.9m) boom with
just under 7dBi forward gain and almost 25dB F/B. The BOLPA came from the
combination of several Monoband logs, arranged upon the same boom. To start
with, 3 x 3el monoband LPDAs where placed one in front of the other for
20m, 15m and 10m. Performance of each was excellent and a bonus band
materialised from this 9-element array; 12m was delivered for free!
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> Therefore, this first pass with 9 elements gave 20m, 15m, 12m and 10m all
in a very short package but 17m was missing. Justin shifted the 20m 3
element cell back on the boom and placed a single element between the 20m
cell and the 15m cell and optimised this element for lowest SWR for 17m
while carefully adjusting the position of the 20m and 15m cells ever side
of it. The result? The BOLPA-10 which covers all bands from 20m through to
10m (usable right up to 30MHz) with exceptional performance throughout.
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> Not only did the director for 20m provide a reflector for 17m and the
first of the 15m elements provide a director for 17m ensuring excellent
results on that band, the dedicated 17m element added an additional element
to the 15m cell (now totalling 4 close-spaced elements) which delivers over
7.5dBi on this band along with 28dB F/B.
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> The first customer reports have confirmed SWR figures on all ham band of
around 1:1.1 with 12m reaching as high as 1:1.3. on the upper end of the HF
spectrum, the BOLPA-10 remains extremely stable across 6 MHz (between 24MHz
and 30MHz) resulting in another benefit on all bands for valve amplifier
users, No retuning because of same-band QSY!
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> Mechanical Construction and Feed Requirements
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> Unlike many traditional LPDAs, the BOLPA-10 does not have a 200Ohm feed
point, like all InnovAntennas Yagis it has a direct, 50Ohm feed and
therefore, simple 1:1 or choke baluns can be used and in turn, this means
higher power handling abilities (5KW+). In order the reduce complexity, the
BOLPA-10 using twin, square booms one about the other which double as the
feed lines between each element which again improves the ability for the
antenna to handle QRO.
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> The BOLPA-10 is the first in a new generation of high performance
directional antennas suited to getting the very best from the very latest
SDR transceivers. More information and ordering can be done via the
InnovAntennas factory in this UK who direct supply with very competitive
shipping prices, the World over.
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http://www.innovantennas.com/antennas-a-accesories/on-line-shop/view/productdetails/virtuemart_product_id/509/virtuemart_category_id/75.html
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> Email: sales  innovantennas.com
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> Tel: +44 203 384 0072
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> Photos:
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> BOL-4 and BOL-3 – Photos of the BOLPA-10 installed at a customer site in
Sweden
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> BOLPDA-PLOT – plot overlay for all bands between 20m and 10m With the
exception of 12m, all bands show F/B well in excess of 20dB
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> --
> António Matias
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> CT1FFU - CR5A
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> http://www.gadgetpriority.pt
> http://www.dxpatrol.pt
> http://www.ct1ffu.com
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> Parque Tecnológico de Óbidos
> Edifícios Centrais, Rua da Criatividade
> 2510-216 Óbidos
> Portugal
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> POBOX-38
> 2504-909
> Caldas da Rainha
> Portugal
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> Coordenadas GPS:
> Latitude= 39.38144
> Longitude= -9.14494
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