Merle,
Great questions.
I have not really tested the actual front to back of the array. I did not
have time. You can adjust it in the field.
The manuals for all the 4sq equipment is available at www.dxengineering.com
. I selected 70 foot sides as that was recommended in the manual. It is a
comprimise for 160 and 80 with 40 thrown in. The results on 40m here in
Colorado have been mixed. It is nice to be able to switch to a different
direction and wipe out qrm so there is a decent amount of F/B. The optimal
side length for 160m is 135 ft.
I am using the active elements both here and Montana. The newer version
swtiches off the elements when not in use and if you use a sequencer you can
install the array within 1/10 wavelength of your transmit antennas if they
are a unity gain antenna. For a 6db gain antenna on 160m you would need to
locate the array 220 ft away. Mine is located over 300 ft away and I do not
use the sequencer.
I believe there are some charts on performance in the manuals but I don't
have them handy to look at.
My shortened 160 vertical lasted all of 3 days in the air before one of our
horses or donkey decided that the guy line was in their way and down it came
in a bent mess :(. The signal to noise ratio of the array is far superior
to the vertical. I hope to put up an inverted L in the next few days so I
might have more observations soon.
The array made it possible to work a number a stations on 80 and 160 that
would never had heard with the vertical or the inv V for 80.
I hope this helps out. I would be happy to answer any other questions.
Mike W0MU
_____
From: Merle Bone [mailto:merlebone@charter.net]
Sent: Wednesday, November 29, 2006 4:50 PM
To: w0mu@w0mu.com
Subject: DX Engineering 4 Sq.
Hi Mike,
I don't really know the answer to your question but I am thinking hard about
putting in a DX Engineering 4 Sq. to compliment my K9AY double loop. I put
the loop up a little over a year ago and I find it to be much better
(Signal/Noise Ratio) then my inverted-L transmit antenna (90 Ft. high
vertical section - rest-45 Ft. - horizontal) on 160M and then my 66 Ft. high
80 Meter vertical - - both made out of #14 copper clad steel wire. It makes
a huge difference here in St. Louis. I am in a reasonably quiet area - with
a 50 acre farm behind my house - and the K9AY loop makes the difference
between making the contact or not - not, if I had to use the transmit
antenna. I have a one button push (Using a Ten-Tec Orion) to compare the
transmit antenna with the K9AY loop. The loop is always better. I have the
loop about 150 Ft. from the house and about 60-70 Ft from the transmit
antenna (I only have a one acre lot). The K9AY loop shows an 18-20Db front
to back ratio.
I am very interested the results you are seeing from the DX Engineering 4
Sq. Are you using the "active antennas" they sell or are you using passive
elements? How did you decide on the 70 Ft. spacing? What does the front to
back ratio look like on 160M and 80M - if you have had a chance to check it.
What are you using for transmit antennas and how does the loop compare to
the transmit antennas for receiving? Does DX Engineering offer any "rough"
performance data or antenna patterns with the antenna? How far away from
your transmit antennas is the 4 Sq. ?
Mike thanks very much for your help in advance. If there is anything you
would like to know about the K9AY double loop just ask.
Thanks & 73,
Merle - W0EWM
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