Good morning Lee and all,
Having got more than 40 replies to my simple questions means that top band
interest is catching up after northern hemisphere summer season, thank you
all!
To summarize:
Almost all of the answers I got regarding DX Engineering 4 square state
excellent performance and pro design but some guys intend to keep their
Beverages as well. (As one ham stated, you can never have too many antennas
for top band)
Quoting a few statements:
Tim, K3LR is using their setup but uses tuned whips which have to be retuned
between CW and SSB top band. From various contests I know that Tim and his
crew do hear very well.
Lee, N8LJ uses tuned 6 metres long whips. He can switch between 160 and 80.
Denny, K8DO says it is better than his bvgs 95% of the time. He has taken
down 8 bvgs.
Mike, K4Ki is very pleased but needed a preamp.
Bob, W9GE is pleased as well.
Tom, N1IN says:
Keep in mind that although I am suggesting the beverages are overall better
than the 4 square except on rare occasions, the fact that they are even
somewhat close is impressive when you consider the 4 square's size. My
Beverage wires take up 8 acres. The 4 square takes up 0.2 acres.
Dean, W5PJR says:
It has been a totally positive experience. It has been in
place for just about two years now and works as advertised. Mine is built on
100' sides. I have one 600' Beverage and it compares favorably with it. If
I were to build another? I would try much smaller spacing in order to have
it be effective on the 30 and 40 meter band. According to theory the only
thing negative about smaller spacings is the output level and thats easy to
fix with a preamp or maybe two.
An old friend from W7 does have difficulties with the performance and
suspects it is due to very poor ground conditions.
Carlos N4IS suggests I try the Waller flag
A few hams suggest I build my own in order to save money which is very
relevant taking into account freight and taxes from US to Sweden.
Bob, W7LR is on his way using partial layout from Lees, K7TJR design for a 4
square.
Regarding thin elements I quote Lee, K7TJR and I have seen some along those
lines in an earlier book someplace.
"I recognize the statements you refer to as being from my recent 8
element antenna article posted to my website. First let me say that I
cannot speak to the Dx Engineering RX 4 square at all as I have no
experience there. I have built a few of my own 4 squares with great results
however. The comments about voltage gain and phase shift apply only to my
system as described in the 8 element article. The Hi-Z amplifier along with
the antenna element mounting arrangement apply a load capacitance to the
antenna element itself. This load capacitance is right at 30pf. The antenna
element itself in the form of a thin 10 foot element has a source series
capacitance of right around 30 pf. This forms a voltage divider of about .5
to 1. A 6 Db loss. If you increase the length and diameter of the element to
20 feet and about 3/4 inch dia. The series capacitance increases to about 60
pf. This reduces the voltage loss to about 3.5 Db. You also get the extra
voltage gain as a result of th
e longer element. In addition I have modeled this system and found a change
in the amplifiers output phase of about 2 degrees going between the two
element sizes. These numbers were important to me in the 8 element design
however it is my opinion that you would likely see no discernable changes in
a simpler 4 square antenna as long as all your elements were reasonably
identical."
73
Lee K7TJR www.k7tjr.com "
Having got all this feedback my own conclusion is to go for a 4 el square.
Buying or building is a matter of time and money.
Once again, thank you all and special thanks to Lee, K7TJR who really
triggered me.
73
Len/SM7BIC
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