HI Dave,
At K3LR the full size four squares are not used for TXing, however I think
they would be very effective - about the same as a 3 element Yagi at one to
two wavelengths high (about the same take off angle).
The transmitting 4 squares compare very well to the active RX vertical
arrays (4 or 8 elements). I would give the performance edge to the active
arrays (such as DXE and HI-Z) as the components used allow much wider
bandwidth and the phasing is much better controlled to optimize the RX
pattern.
I have never tried the 4 or 8 element active RX arrays above 7 MHz - as my
large element spacing is optimized for 160 and 80 meter band best
performance.
73,
Tim K3LR
-----Original Message-----
From: CQ-Contest [mailto:cq-contest-bounces@contesting.com] On Behalf Of
David Siddall
Sent: Wednesday, September 03, 2014 12:54 PM
To: cq-contest@contesting.com
Cc: k3lr@k3lr.com
Subject: Re: [CQ-Contest] High band rx arrays for contesting
Hi Tim, I thought you might be lurking here.
You addressed using the 4-squares for receiving. Two more q.'s:
(1) how do they compare to beams for transmitting (on higher
bands,10-15-20) ?
(2) how do your transmitting 4-squares compare to a 4-square active receive
array on same higher bands, or to an 8-circle array on higher bands (such
as the DXE packages)?
73, Dave K3ZJ
On Mon, Sep 1, 2014 at 8:43 PM, Tim Duffy <k3lr@k3lr.com> wrote:
> Hello Mike and Dave!
>
> We have found that 4 squares on 20, 15 and 10 meters work very well for
> hearing DX stations. Quick rotation is certainly a plus. It is amazing how
> close their performance is - when compared to some of the horizontal
> Yagi's.
>
> As is the case with low frequency 4 squares, the ground radial field is
> critical to getting best performance (gain). For these three HF bands (20,
> 15 and 10) at K3LR, the 4 squares have 120 radials that are one half
> wavelength long under each quarter wave element. All over lapping radials
> are silver soldered at their junctions. Ground losses must be minimized.
>
> We have been using quarter wave element four square vertical arrays on all
> HF contest bands (except 160 meters) for more than 20 years. They are very
> effective for DX!
>
> 73,
> Tim K3LR
>
> -----Original Message-----
> From: CQ-Contest [mailto:cq-contest-bounces@contesting.com] On Behalf Of
> David Siddall
> Sent: Monday, September 01, 2014 5:47 PM
> To: cq-contest@contesting.com
> Cc: W0MU Mike Fatchett
> Subject: Re: [CQ-Contest] High band rx arrays for contesting
>
> K3LR has 4-squares on the high bands (in addition to a multiple OWAs
etc.).
>
>
> On Mon, Sep 1, 2014 at 12:51 PM, W0MU Mike Fatchett <w0mu@w0mu.com> wrote:
>
> > I have switched to many different receiving antennas on the high bands.
> > The ability to listen in many different direction with the array would
be
> a
> > plus. It never fails that when I turn my beam to EU, AF or SA call. I
> > don't see why a circle or 4 sq array would not work on the high bands.
> > Finding the sweet spot for 20, 15 and 10 might be more challenging.
> >
> > K3LR or W3LPL or others might have comments based on modeling.
> >
> > Mike W0MU
> >
> > On 8/31/2014 11:39 PM, Bob Kupps via CQ-Contest wrote:
> >
> >> Hi we enjoy a relatively high level of propagated QRN here right up
> >> through 30 mHz. We have some good transmitting antennas that certainly
> help
> >> but even using stacks we get some very deep mid-angle nulls with our
> flat
> >> Fresnel zone. The phased vertical rx arrays look very attractive with a
> >> beam width comparable to our yagis but a much nicer elevation profile
> and
> >> F/B. Plus the ability to switch directions very rapidly. The downside
> might
> >> be their low sensitivity below 6-7 degrees elevation compared to the
> high
> >> horizontal antennas.
> >>
> >> Does anyone have experience using rx arrays on the high bands in
> contests?
> >>
> >> 73 Bob HS0ZIA
> >> _______________________________________________
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> >>
> >
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