Hi all
I have recently built a 4 Square, completely home brew, including phase
unit. In terms of construction it was pretty straight foreword, using
ON4UN's book and the TK5EP Website (4 Square page).
The phase unit is identical to the Comtek unit, and uses the "Collins
method". This method is very forgiving and a very reproducible design.
In comparison to a sloping dipole, a single quarter wave vertical, a
full size diamond loop and the 40 2 CD I once had, it has some
advantages and disadvantages.
Located in Europe, the ability to reduce Eu noise by 10 - 20dB at night
is excellent, and a big improvement over the other antennas. In terms of
DX working it really gets going when stations are 2,000 miles plus away.
The reason for both of these features is simply radiation angle. The
radiation angle of a 4 Square can be much better than a 2 element Yagi
at times. The better each & radial system you put in, the better the 4
Square works. But you need to be careful, as I found that the 4 Square
has a narrow bandwidth offering maximum gain, so whilst you think its
working great, it isn't. Move 20KHz up the band, and it will really
sing. This is the effects of ground & radials.
The 402CD I had, was up at 50 feet, and put a huge signal into the rest
of Europe from here in Wales, but it was poor on DX. The reason is again
take off angle.
So I think the situation can be summed up by considering what sort of
ground you have, the position & terrain of your site, out to say 10
maybe 20 wavelengths away, and then model the take off angles.Try a
quarter wave vertical with say 4 elevated radials, then lower the
radials to the ground, and you'll see the effects of ground & radials
upon bandwidth & take off angles. You'll then figure out if a 4 Square
will work at your location.
A 2 Element beam at my location didn't cut it,for a number of reasons,
apart from performance (maintenance, high winds, getting it high enough
etc).
Happy to discuss further, or if you want details on how to build the
phase unit.
73
Adrian
MW1LCR / GW9X
On 29/09/2012 20:42, John Frazier wrote:
Anyone have real-world experience with phased verticals on 40m? Actual
comparisons to high dipole, etc would be greatly appreciated.
Bottom line...was it worth the effort?
73 John W4II
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